GSA Practice Set 4 – General Science & Ability (20 Original MCQs Explained)

This is GSA Practice Set 4 — 20 original MCQs for General Science & Ability (CSS Compulsory, 100 marks). 10 Science (Q1–Q10) + 10 Ability (Q11–Q20). Attempt all 20 in 25 minutes without looking at the answers, then check the explained answers. These are original practice questions, not copied from FPSC papers or competitor question banks, and this site is not affiliated with FPSC. Scoring: 18–20 = strong. 15–17 = good. 12–14 = fair, revise the ones you missed. Below 12 = study the weak-section review, then re-attempt in 2 days.

Science (Q1–Q10)

Q1. What is the chemical symbol for sodium? A) So B) Na C) Sd D) N

Q2. Which is the hardest natural substance? A) Gold B) Iron C) Diamond D) Quartz

Q3. Which blood cells carry oxygen around the body? A) White blood cells B) Red blood cells C) Platelets D) Plasma cells

Q4. What is the unit of electric current? A) Volt B) Ohm C) Watt D) Ampere

Q5. Which planet is called the Red Planet? A) Venus B) Mars C) Jupiter D) Saturn

Q6. Which gas do plants use for photosynthesis? A) Oxygen B) Nitrogen C) Carbon dioxide D) Hydrogen

Q7. Which is the largest organ of the human body? A) Liver B) Heart C) Skin D) Lung

Q8. What is the boiling point of water at sea level? A) 90°C B) 95°C C) 100°C D) 110°C

Q9. Which vitamin deficiency causes scurvy? A) Vitamin A B) Vitamin B C) Vitamin C D) Vitamin D

Q10. What is the main function of white blood cells? A) Carry oxygen B) Fight infection / immunity C) Clot blood D) Carry nutrients

Ability (Q11–Q20)

Q11. If a pen costs Rs 25, what is the cost of 8 pens (same price)? A) Rs 150 B) Rs 175 C) Rs 200 D) Rs 225

Q12. What is 40% of 150? A) 40 B) 50 C) 60 D) 70

Q13. If 4x + 6 = 22, what is x? A) 3 B) 4 C) 5 D) 6

Q14. Next number in the series: 1, 4, 9, 16, 25, ? A) 30 B) 32 C) 36 D) 49

Q15. What is the perimeter of a square with side 6 cm? A) 12 cm B) 18 cm C) 24 cm D) 36 cm

Q16. Which of these is an odd number? A) 24 B) 26 C) 27 D) 28

Q17. If a : b = 3 : 4 and b = 12, what is a? A) 6 B) 8 C) 9 D) 10

Q18. Which of these is a composite number? A) 13 B) 17 C) 19 D) 21

Q19. What is the average of 5, 15, and 25? A) 10 B) 15 C) 20 D) 25

Q20. If a bus travels 240 km in 4 hours, what is its speed? A) 40 km/h B) 50 km/h C) 60 km/h D) 80 km/h

Answer Key + Explained Answers

Q1 – B) Na. Sodium = Na (from Latin Natrium). So / Sd are not symbols; N = nitrogen.

Q2 – C) Diamond. Diamond is the hardest natural substance (10 on Mohs scale). Gold and iron are soft metals; quartz is hard (7) but softer than diamond.

Q3 – B) Red blood cells. RBCs carry oxygen (via haemoglobin). WBCs fight infection; platelets clot blood; plasma is the fluid.

Q4 – D) Ampere. Ampere (A) is the unit of current. Volt = potential, Ohm = resistance, Watt = power.

Q5 – B) Mars. Mars is the Red Planet (iron oxide / rust on surface). Venus is Morning Star; Jupiter is largest; Saturn has rings.

Q6 – C) Carbon dioxide. Plants use CO2 + water + sunlight for photosynthesis, producing oxygen. Oxygen is the product, not the input; nitrogen is in air but not used for photosynthesis; hydrogen is not used directly.

Q7 – C) Skin. Skin is the largest organ (by area and weight). Liver is largest internal organ; heart and lung are smaller.

Q8 – C) 100°C. Water boils at 100°C (212°F) at sea level (1 atm). At higher altitude, boiling point is lower. 90/95 are too low; 110 is too high.

Q9 – C) Vitamin C. Scurvy = Vitamin C deficiency (bleeding gums, slow healing). Vitamin A = night blindness; B = beriberi; D = rickets.

Q10 – B) Fight infection / immunity. WBCs are the immune system. RBCs carry oxygen; platelets clot blood; plasma carries nutrients.

Q11 – C) Rs 200. 8 × 25 = 200.

Q12 – C) 60. 40% of 150 = 0.40 × 150 = 60.

Q13 – B) 4. 4x + 6 = 22 → 4x = 16 → x = 4.

Q14 – C) 36. Series is squares: 1²=1, 2²=4, 3²=9, 4²=16, 5²=25, 6²=36. (49 is 7², two steps ahead.)

Q15 – C) 24 cm. Perimeter of square = 4 × side = 4 × 6 = 24 cm. (36 is area: 6 × 6 = 36 sq cm.)

Q16 – C) 27. Odd numbers are not divisible by 2. 27 is odd. 24, 26, 28 are even.

Q17 – C) 9. a : b = 3 : 4 means a = (3/4) × b = 0.75 × 12 = 9.

Q18 – D) 21. Composite = has factors besides 1 and itself. 21 = 3 × 7. 13, 17, 19 are prime.

Q19 – B) 15. Average = (5 + 15 + 25) ÷ 3 = 45 ÷ 3 = 15.

Q20 – C) 60 km/h. Speed = distance ÷ time = 240 ÷ 4 = 60 km/h.

Weak-Section Review

Which section did you score lowest in? Write the 3 questions you missed, the correct answers, and one line for each explaining why. Science: revise symbols (Na, Au, Ag, Fe), units (Ampere, Volt, Ohm, Watt), planets (Mars Red Planet), organs (skin largest), vitamins (C = scurvy). Ability: revise percentages, ratios, averages, speed = distance ÷ time, perimeter vs area, squares, prime vs composite, odd vs even. Re-attempt this set in 2 days.

These are original practice questions written for csspastpapers.pk. They are not FPSC official questions, and this site is not affiliated with FPSC.

Related: GSA past papers, CSS syllabus, GSA Practice Set 1, GSA Practice Set 2, GSA Practice Set 3, and MPT Practice Set 1.