Aspirants who appeared for the TNPSC Group 2 Prelims exam on September 28, 2025, can now check the unofficial answer key for questions 121 to 130 from the General Studies paper. This TNPSC Group 2 Answer Key 2025 provides the correct option, detailed step-by-step solutions, and important key notes to help you analyse your performance and estimate your score.
TNPSC Group 2 Answer Key 2025: An Overview
| Aspect | Details |
|---|---|
| Conducting Body | Tamil Nadu Public Service Commission (TNPSC) |
| Exam Name | TNPSC Group 2 & 2A Prelims 2025 |
| Total Vacancies | 645 |
| Exam Date | September 28, 2025 |
| Official Answer Key Release | First week of October 2025 (Expected) |
| Official Website | tnpsc.gov.in |
How to Use the TNPSC Group 2 Answer Key 2025
Using this answer key for questions 121 to 130 can effectively help you calculate an estimated score and analyse your performance in the exam. Follow these simple steps:
- Compare Your Answers: Go through each question one by one and compare the option you marked in the exam with the “Correct Answer” provided in our key.
- Follow the Official Marking Scheme: To calculate your score, you need to know how the TNPSC Group 2 Prelims paper is graded.
- Correct Answer: You are awarded 1.5 marks.
- Incorrect Answer / Unanswered Question: There is no negative marking. You get 0 marks.
- Calculate Your Estimated Score: Use this straightforward formula to find your probable score: Estimated Score=(Total Number of Correct Answers)×1.5 For example, if you answered 120 questions correctly out of 200, your estimated score would be 120×1.5=180.
- Analyse and Learn: Don’t just stop at the score.
- For questions you got wrong, read our “Detailed Solutions & Key Notes” to understand where you made a mistake.
- This analysis helps you identify your weaker subjects and topics, which is crucial for preparing for the Mains exam or future attempts.
Disclaimer: Please remember that this is an unofficial answer key created for your immediate reference. There may be slight variations from the official key that will be released by the TNPSC. Your final score will be based on the official TNPSC answer key only.
TNPSC Group 2 Prelims 2025: General Studies Answer Key (Questions 121-130) Solutions & Key Notes
TNPSC Group 2 Answer Key 2025 Solutions: Below are the detailed step-by-step explanations for Questions 121–130. These FAQs cover reasoning, maths, Tamil grammar, and general studies answers as per the official exam pattern. Candidates preparing for the upcoming TNPSC Group exams can use these solutions for practice and revision.
Q.121. The cost of 15 kg of sugar is Rs.255, the cost of 17 kg of tea is Rs.1,615 and the cost of 22 kg of rice is Rs.572. What is the total cost of 18 kg of sugar, 21 kg of tea and 27 kg of
rice?
(A) Rs.2,442
(B) Rs.3,923
(C) Rs.3,003
(D) Rs.2,932
(E) Answer not known
Correct Answer: (C) Rs. 3,003
Step-by-Step Solution:
Alright, let’s carefully solve step by step:
Given:
- Cost of 15 kg sugar = Rs. 255
- Cost of 17 kg tea = Rs. 1,615
- Cost of 22 kg rice = Rs. 572
We need: Cost of 18 kg sugar + 21 kg tea + 27 kg rice.
Step 1: Find unit prices per kg
- Sugar price per kg = 255 ÷ 15 = Rs. 17
- Tea price per kg = 1615 ÷ 17 = Rs. 95
- Rice price per kg = 572 ÷ 22 = Rs. 26
Step 2: Multiply by required quantities
- 18 kg sugar = 18 × 17 = Rs. 306
- 21 kg tea = 21 × 95 = Rs. 1,995
- 27 kg rice = 27 × 26 = Rs. 702
Step 3: Add them up
306 + 1995 + 702 = Rs. 3,003
Q.122. The income of a person is increased by 10% and then decreased by 10%. Find the change in his income in percentage.
(A) reduced by 1%
(B) increased by 1%
(C) reduced by 2%
(D) increased by 2%
(E) Answer not known
Correct Answer: A) reduced by 1%
Step-by-Step Solution:
Step 1: Assume the initial income
Let the initial income = Rs. 100 (We can assume any value; 100 makes calculations easier)
Step 2: Apply 10% increase
Income after 10% increase = 100 + (10% of 100)
- = 100 + (10/100 × 100)
- = 100 + 10
- = Rs. 110
Step 3: Apply 10% decrease on the new income
Income after 10% decrease = 110 – (10% of 110)
- = 110 – (10/100 × 110)
- = 110 – 11
- = Rs. 99
Step 4: Calculate the net change
Net change = Final income – Initial income
- = 99 – 100
- = -1
Step 5: Find percentage change
Percentage change = (Net change / Initial income) × 100
- = (-1 / 100) × 100
- = -1%
The negative sign indicates a reduction.
Final Answer: The income is reduced by 1%
Q.123. Ravi ranks 9th in a class of 45 students. There are 18 students below Raj Rankwise.
How many students are there between Ravi and Raj rankwise?
(A) 27
(B) 17
(C) 18
(D) 19
(E) Answer not known
Correct Answer: (B) 17
Step-by-Step Solution:
Let’s solve this step-by-step using rank positions.
Step 1: Understand Ravi’s rank
Ravi ranks 9th from the top in a class of 45 students.
Step 2: Determine Raj’s rank
If 18 students are below Raj, then Raj’s rank from the top is:
Raj’s rank = 45 – 18 = 27
Step 3: Find number of students between Ravi and Raj
Ravi is 9th, Raj is 27th. So the number of students between them is:
27 – 9 – 1 = 17
We subtract 1 because we want the count of students between them, not including Ravi or Raj.
So there are 17 students between Ravi (9th) and Raj (27th).
Key Formula:
Number of students between two ranks = |Rank₁ – Rank₂| – 1
Important Points:
- “Below” means lower rank (higher number)
- To find rank from “students below”: Rank = Total students – Students below
- Always subtract 1 when finding elements “between” two positions (excluding the endpoints)
Q.124. If DANGER is coded as 10-7-20-13-11-24, then the code of ‘MACHINE’ in the same
code is
(A) 13-7-20-9-11-25-15
(B) 13-7-20-10-11-25-15
(C) 19-7-9-15-14-11-20
(D) 19-7-9-14-15-20-11
(E) Answer not known
Correct Answer: (D) 19-7-9-14-15-20-11
Step-by-Step Solution:
Step 1: Find the coding pattern
Word = DANGER
Code = 10-7-20-13-11-24
Let’s check each letter.
- D (4th letter) → 10
- A (1st letter) → 7
- N (14th letter) → 20
- G (7th letter) → 13
- E (5th letter) → 11
- R (18th letter) → 24
👉 Each code = Alphabet position + 6.
Check quickly:
- D = 4 → 4+6 = 10
- A = 1 → 1+6 = 7
- N = 14 → 14+6 = 20
- G = 7 → 7+6 = 13
- E = 5 → 5+6 = 11
- R = 18 → 18+6 = 24
So rule is letter position + 6.
Step 2: Apply rule to “MACHINE”
Letters & positions:
- M = 13 → 13+6 = 19
- A = 1 → 1+6 = 7
- C = 3 → 3+6 = 9
- H = 8 → 8+6 = 14
- I = 9 → 9+6 = 15
- N = 14 → 14+6 = 20
- E = 5 → 5+6 = 11
Code = 19-7-9-14-15-20-11
Quick Recall: Coding Pattern: Alphabet Position + 6
- Formula: Code = (Position of letter in alphabet) + 6
- This is a simple substitution cipher with a fixed shift of 6 positions
Q.125. Carbon serves for the following purpose/purposes in living organisms:
(1) It’s a structural component of organic molecule
(2) Helps to bind with other molecules
(3) Gives flexibility to the form and function of Biomolecules such as DNA and RNA
Options:
(A) (1) alone
(B) (2) alone
(C) (3) alone
(D) (1), (2) and (3)
(E) Answer not known
Correct Answer: (D) (1), (2) and (3)
Step-by-Step Analysis:
Statement (1): Carbon is a structural component of organic molecules ✓
- TRUE: Carbon forms the backbone of all organic molecules including carbohydrates, proteins, lipids, and nucleic acids
- Carbon’s ability to form four covalent bonds makes it ideal for building complex molecules
Statement (2): Helps to bind with other molecules ✓
- TRUE: Carbon can form stable covalent bonds with hydrogen, oxygen, nitrogen, sulfur, and other carbon atoms
- This bonding capability allows formation of diverse molecular structures
Statement (3): Gives flexibility to form and function of biomolecules such as DNA and RNA ✓
- TRUE: The carbon-carbon bonds in the sugar-phosphate backbone of DNA/RNA allow rotational freedom
- This flexibility enables DNA to form double helix structure and undergo conformational changes
- Carbon chains can form linear, branched, or ring structures providing structural diversity
All three statements are correct.
Quick Revision Guide:
- Essential for DNA/RNA structure and cellular energy molecules (ATP, glucose).
- Carbon = backbone of life.
- Tetravalent → forms 4 bonds.
- Versatile → chains, rings, branches.
- Found in carbohydrates, proteins, lipids, nucleic acids.
Exam Tip:
- Carbon is called the “building block of life.”
- Think of it as the skeleton with functional groups attached.
- When asked about carbon’s role → structure + bonding + flexibility.
- “All of the above” answers are often correct in such questions.
- Always remember: Carbon’s tetravalency makes it the most versatile element in biology.
👉 If multiple roles are listed → likely all are correct.
Q.126. Which of the following statements are true?
Essential properties of Magnetic Materials to be an Electromagnet.
(I) Narrow hysteresis loop
(II) High permeability
(III) High coercivity
(IV) Low retentivity
Options:
(A) (I) alone
(B) Both II and III are correct
(C) II, III, and IV are correct
(D) I, II. and IV are correct
(E) Answer not known
Correct Answer: (D) I, II. and IV are correct
Explanation:
To be an effective electromagnet, a magnetic material should have properties that allow it to magnetize quickly and demagnetize easily. Here’s how each statement fits:
(I) Narrow hysteresis loop ✅
- Electromagnets need to magnetize and demagnetize easily when current is switched on/off
- A narrow hysteresis loop means low energy loss during magnetisation cycles
- This allows the material to quickly respond to changes in magnetic field
(II) High permeability ✅
- Allows magnetic field lines to pass through easily.
- Ensures strong magnetic field generation with minimal current.
- Materials like soft iron have high permeability, making them ideal for electromagnet cores
(III) High coercivity ❌ (INCORRECT)
- Coercivity is the resistance to becoming demagnetized.
- High coercivity is bad for electromagnets because it makes switching off the magnet harder.
- Electromagnets need LOW coercivity so they can be easily demagnetized when current is turned off
- High coercivity is desired for permanent magnets, not electromagnets
(IV) Low retentivity ✅
- Retentivity is the ability to retain magnetization after the external field is removed
- Electromagnets need LOW retentivity so they don’t remain magnetized after current is switched off
- This ensures the electromagnet can be turned on and off effectively
Visual diagram of hysteresis loops
Quick Revision Guide:
| Property | Electromagnet Needs | Why? |
|---|---|---|
| Hysteresis Loop | Narrow | Low energy loss |
| Permeability | High | Strong field with less current |
| Coercivity | Low | Easy to demagnetize |
| Retentivity | Low | No residual magnetism after switch-off |
Exam Tip:
For electromagnets, think fast response and low loss. Avoid properties that make magnetism “stick” like high coercivity or high retentivity.
Q.127. Consider the statements about the soil and choose the right answer:
(1) The soils of northern plains are largely deposited by Himalayan Rivers.
(2) The presence of Iron Oxide is more in a soil popularly known as black soil
(3) The soil derived from deccan trap is fertile and has high moisture holding
capacity.
Options:
(A) (1) is true/correct
(B) (1) and (3) are correct
(C) (2) and (3) are correct
(D) (1) and (2) are correct
(E) Answer not known
Correct Answer: B) (1) and (3) are correct
Explanation:
Statement (1): The soils of northern plains are largely deposited by Himalayan Rivers ✓ CORRECT
- The soils of the vast northern plains are alluvial soils, which have been deposited by the three major Himalayan river systems – the Indus, the Ganga, and the Brahmaputra. This makes them extremely fertile.
Statement (2): The presence of Iron Oxide is more in a soil popularly known as black soil ✗ INCORRECT
- Red and Laterite soils are rich in iron oxide, which gives them their characteristic reddish color. Black soil (Regur soil) gets its color from high clay content and titaniferous magnetite, not iron oxide.
Statement (3): The soil derived from Deccan trap is fertile and has high moisture holding capacity ✓ CORRECT
- The soil derived from the Deccan trap (volcanic basalt rocks) is black soil. It is famous for its high fertility and excellent moisture-holding capacity, making it ideal for growing cotton.
Key Points to Remember:
Soil Types in India:
- Alluvial Soil: Northern plains, river deposits, highly fertile
- Black Soil: Deccan plateau, basaltic origin, high water retention, good for cotton
- Red Soil: High iron oxide content, reddish color, less fertile
- Laterite Soil: Heavy rainfall areas, iron and aluminum rich, acidic
- Desert Soil: Arid regions, sandy, low fertility
Colour Indicators of Soil:
- Black → Clay and humus content (Deccan trap soils)
- Red/Yellow → Iron oxide content (oxidized soils)
- Alluvial → Light colored, mixture of sand, silt, clay
Q.128. Choose the right matches among type:
| (1) Permanent Settlement | – Lord Curzon |
| (2) Partition of Bengal | – Cornwallis |
| (3) Ryotwari System | – Munro |
| (4) Network of Railways | – Dalhousie |
(A) (1) and (3) are correct
(B) (1) and (2) are correct
(C) (2) and (3) are correct
(D) (3) and (4) are correct
(E) Answer not known
Correct Answer: (D) (3) and (4) are correct
Step-by-Step Analysis:
Statement (1): Permanent Settlement – Lord Curzon ❌ INCORRECT
- Permanent Settlement (Zamindari System) was introduced by Lord Cornwallis in 1793
- It was implemented in Bengal, Bihar, Odisha, and parts of Northern India
- Lord Curzon (1899-1905) is known for partitioning Bengal, not Permanent Settlement
- This pairing is WRONG
Statement (2): Partition of Bengal – Cornwallis ❌ INCORRECT
- Partition of Bengal was done by Lord Curzon in 1905
- Cornwallis (1786-1793) introduced the Permanent Settlement
- The roles are reversed in this statement
- This pairing is WRONG
Statement (3): Ryotwari System – Munro ✅ CORRECT
- Ryotwari System was introduced by Sir Thomas Munro (and Alexander Read)
- Implemented in Madras (1820), Bombay, and parts of Assam
- Under this system, settlement was made directly with the cultivators (ryots)
- This pairing is CORRECT
Statement (4): Network of Railways – Dalhousie ✅ CORRECT
- Lord Dalhousie (1848-1856) introduced railways in India
- First railway line: Bombay to Thane (1853)
- Dalhousie is known as the “Father of Indian Railways“
- He also introduced telegraphs, postal system, and modern communication
- This pairing is CORRECT
Quick Revision Guide:
Important Governor-Generals and Their Reforms:
Lord Cornwallis (1786-1793):
- Permanent Settlement (1793)
- Separation of revenue and judicial functions
- Police reforms
Lord Dalhousie (1848-1856):
- Railways (1853)
- Telegraph and postal system
- Doctrine of Lapse
- Widow Remarriage Act (1856)
Lord Curzon (1899-1905):
- Partition of Bengal (1905)
- Ancient Monuments Preservation Act (1904)
- Universities Act (1904)
- Police Commission (1902)
Land Revenue Systems:
- Permanent Settlement – Cornwallis (1793) – Bengal, Bihar
- Ryotwari System – Munro – Madras, Bombay
- Mahalwari System – Holt Mackenzie, Martin Bird – North-West, Punjab
Exam Tip:
- Remember the “3 C’s”: Cornwallis – Curzon – Confusion! These two are often mixed up
- Cornwallis = Permanent (1793), Curzon = Partition (1905)
- Dalhousie = Development (Railways, Telegraph, Modern infrastructure)
- Munro = Ryot (direct settlement with cultivators)
- Use mnemonics: “Dalhousie Developed railways” or “Munro met Ryots”
Q.129. Arrange the following in chronological order:
(1) The Indian National Army Trial
(2) Formation of Indian National Army
(3) The Royal Indian Air Force
(4) C. Rajagopalachari’s Formula.
Options:
(A) (4), (2), (1), (3)
(B) (2), (1), (3), (4)
(C) (3), (2), (4), (1)
(D) (1), (2), (3), (4)
(E) Answer not known
Correct Answer: (C) (3), (2), (4), (1)
Chronological Breakdown:
Chronological Order:
(3) RIAF (1932) → (2) INA Formation (1942) → (4) CR Formula (1944) → (1) INA Trial (1945–46)
(4) C. Rajagopalachari’s Formula – 1944 (April)
- Also known as C.R. Formula or Rajaji Formula
- Proposed by C. Rajagopalachari to resolve the deadlock between Congress and Muslim League
- Suggested plebiscite in Muslim-majority areas after independence
- This came FIRST
(2) Formation of Indian National Army (INA) – 1942 (initially) and 1943 (under Subhas Chandra Bose)
- First formed by Captain Mohan Singh in 1942 with Japanese assistance
- Reorganized and revitalized by Netaji Subhas Chandra Bose in 1943
- INA was formed to fight for Indian independence
- This came SECOND
(1) The Indian National Army Trial (Red Fort Trials) – November 1945 to May 1946
- Trials of INA officers (Shah Nawaz Khan, Prem Sahgal, Gurbaksh Singh Dhillon) at Red Fort, Delhi
- Charged with treason and waging war against the King
- Created nationwide protests and strengthened independence movement
- This came THIRD
(3) The Royal Indian Air Force – 1932
- Formation: Established on 8 October 1932 as the Indian Air Force (IAF) with six officers and 19 airmen, initially as an auxiliary arm of the Royal Air Force (RAF).
- Royal Title: In recognition of its service during World War II, King George VI conferred the title “Royal” in 1945, making it the Royal Indian Air Force (RIAF).
- Transition: After India gained independence in 1947 and became a republic in 1950, the prefix “Royal” was dropped, and it became simply the Indian Air Force (IAF)
Chronological Breakdown:
- (3) The Royal Indian Air Force: Established in 1932.
- (2) Formation of Indian National Army: Initially formed in 1942.
- (4) C. Rajagopalachari’s Formula: Proposed in 1944.
- (1) The Indian National Army Trial: Began in November 1945.
Key Timeline (1942-1946):
- 1942: Quit India Movement, Formation of INA (Mohan Singh)
- 1943: INA reorganized under Subhas Chandra Bose
- 1944: C.R. Formula proposed (April)
- 1945: INA Trials begin (November), World War II ends
- 1946: INA Trials continue, RIN Mutiny (February), RIAF Mutiny (February), Cabinet Mission (March)
Q.130. Choose the true statement(s) about the Fundamental Duties:
(1) To protect the Sovereignty, Unity and Integrity of India.
(2) To protect and improve the Natural Environment.
(3) To preserve the rich heritage of our composite culture.
(4) To safeguard private property.
Options:
(A) (1) and (2) only
(B) (2) and (3) only
(C) (1), (2) and (3) only
(D) (2), (3) and (4) only
(E) Answer not known
Correct Answer: (C) (1), (2) and (3) only
Explanation:
Let me verify each statement against the Fundamental Duties listed in Article 51A of the Indian Constitution:
Statement (1): To protect the Sovereignty, Unity and Integrity of India ✓ TRUE
- This is explicitly mentioned in Article 51A(c)
- Exact wording: “to uphold and protect the sovereignty, unity and integrity of India”
- This is a FUNDAMENTAL DUTY
Statement (2): To protect and improve the Natural Environment ✓ TRUE
- This is explicitly mentioned in Article 51A(g)
- Exact wording: “to protect and improve the natural environment including forests, lakes, rivers and wild life, and to have compassion for living creatures”
- This is a FUNDAMENTAL DUTY
Statement (3): To preserve the rich heritage of our composite culture ✓ TRUE
- This is explicitly mentioned in Article 51A(f)
- Exact wording: “to value and preserve the rich heritage of our composite culture”
- This is a FUNDAMENTAL DUTY
Statement (4): To safeguard private property ❌ FALSE
- This is NOT a Fundamental Duty
- There is NO mention of safeguarding private property in Article 51A
- In fact, Right to Property was removed from Fundamental Rights in 1978 (44th Amendment) and made a Constitutional Right under Article 300A
- This is NOT a FUNDAMENTAL DUTY
Quick Revision Guide/Key Notes:
Fundamental Duties (Article 51A) – 11 Duties:
Added by 42nd Amendment (1976) – Originally 10 duties 86th Amendment (2002) added the 11th duty
The 11 Fundamental Duties:
- Abide by Constitution – Respect its ideals, institutions, National Flag and National Anthem
- Freedom struggle ideals – Cherish and follow noble ideals of the freedom struggle
- Sovereignty, Unity, Integrity – Uphold and protect sovereignty, unity and integrity of India
- Defend the country – Defend the country and render national service when called upon
- Promote harmony – Promote harmony and spirit of common brotherhood, transcending religious, linguistic and regional diversities; renounce practices derogatory to women
- Preserve composite culture – Value and preserve the rich heritage of our composite culture
- Protect environment – Protect and improve natural environment including forests, lakes, rivers, wildlife; have compassion for living creatures
- Scientific temper – Develop scientific temper, humanism and spirit of inquiry and reform
- Safeguard public property – Safeguard public property and abjure violence
- Strive for excellence – Strive towards excellence in all spheres of individual and collective activity
- Education for children (86th Amendment, 2002) – Provide opportunities for education to children between 6-14 years
Key Points:
- Fundamental Duties were inspired by the Constitution of USSR (former Soviet Union)
- Recommended by Swaran Singh Committee (1976)
- They are non-justiciable (cannot be enforced by courts)
- However, courts consider them while interpreting laws
- Statement (4) mentions private property – this is incorrect; duty is to safeguard PUBLIC property (Duty #9)
Exam Tip:
- Remember: PUBLIC property (Fundamental Duty) vs PRIVATE property (NOT a Fundamental Duty)
- Focus on the three key environmental/cultural duties: Environment, Composite Culture, Scientific Temper
- The 11th duty (education) was added later in 2002
What’s Next After Checking the TNPSC Group 2 Answer Key 2025?
After estimating your score with the unofficial answer key, follow these crucial steps in the TNPSC Group 2 selection process:
- Wait for the Official Answer Key: TNPSC will release it a few days after the exam. Re-check your responses carefully.
- Challenge Window: Raise objections (if needed) with valid proof during the official challenge period.
- Prelims Result & Cut-Off: Based on the final key, TNPSC will announce results and category-wise cut-off marks.
- Start Mains Preparation Early: Don’t wait for results if your score is above the expected cut-off. Focus on:
- Paper I: Tamil Eligibility Test (descriptive)
- Paper II: General Studies (descriptive – polity, science & tech, Tamil society)
- Stay Updated: Track announcements, hall tickets, and exam dates on the official TNPSC website.
👉 By preparing ahead, you’ll gain an edge in the competition and move one step closer to success in the TNPSC Group 2 Mains exam.
We hope this detailed analysis of questions 121-130 from the TNPSC Group 2 General Studies paper helps you in your score estimation. Remember to use this as a reference and wait for the official key from TNPSC for the final confirmation.
What’s Next?
- Wait for the Official Answer Key: TNPSC will release the official answer key soon. Use it for final verification.
- Prepare to Raise Objections: If you find discrepancies in the official key, be ready to use the challenge window with valid proof.
- Start Your Mains Prep Now: If your score looks promising, don’t wait for the official results. Begin your preparation for the Mains descriptive papers immediately.
- Stay Officially Updated: Keep tracking the official TNPSC website for announcements on results, cut-offs, and Mains exam dates.
We hope this detailed analysis helps you! Leave a comment below with your estimated score!