20 Most Repeated Everyday Science MCQs for NTS, CSS, PMS, KPPSC, PPSC, ETEA, SPSC, BPSC, and FPSC Tests

Here are 20 most repeated Everyday Science MCQs designed specifically for competitive exams like NTS, CSS, PMS, KPPSC, PPSC, ETEA, SPSC, BPSC, and FPSC. These specific Everyday Science MCQs appear frequently across various testing boards in Pakistan.

Most Repeated Everyday Science MCQs 

1. Which gas is the most abundant in the Earth's atmosphere?

A) Oxygen
B) Carbon Dioxide
C) Nitrogen
D) Hydrogen
Correct Answer: C) Nitrogen

Explanation: Nitrogen makes up approximately 78% of the Earth's atmosphere, followed by oxygen at roughly 21%.

2. A deficiency in Vitamin D causes which of the following diseases?

A) Scurvy
B) Rickets
C) Night Blindness
D) Beriberi
Correct Answer: B) Rickets

Explanation: Vitamin D is crucial for calcium absorption. Its deficiency leads to rickets in children (softening of bones) and osteomalacia in adults. Scurvy is caused by Vitamin C deficiency, and night blindness by Vitamin A deficiency.

3. What is the SI unit of electric current?

A) Volt
B) Ampere
C) Ohm
D) Watt
Correct Answer: B) Ampere

Explanation: The Ampere (often shortened to "amp") is the base unit of electric current in the International System of Units (SI). Volts measure voltage, Ohms measure resistance, and Watts measure power.

4. Which gland is commonly referred to as the "master gland" of the human body?

A) Thyroid gland
B) Pancreas
C) Pituitary gland
D) Adrenal gland
Correct Answer: C) Pituitary gland

Explanation: The pituitary gland is called the master gland because the hormones it produces control and regulate the functions of many other endocrine glands in the body.

5. Sound travels fastest in which of the following mediums?

A) Air
B) Water
C) Vacuum
D) Steel
Correct Answer: D) Steel

Explanation: Sound waves are mechanical waves that require a medium to travel. They travel fastest in solids (like steel) because the molecules are tightly packed together, allowing the vibration to transfer quickly. Sound cannot travel in a vacuum at all.

6. Which planet in our solar system is known as the "Red Planet"?

A) Venus
B) Jupiter
C) Mars
D) Saturn
Correct Answer: C) Mars

Explanation: Mars appears red due to the widespread presence of iron oxide (rust) on its surface.

7. A person with which blood group is considered a "Universal Donor"?

A) A positive
B) AB positive
C) O negative
D) B negative
Correct Answer: C) O negative

Explanation: O negative blood lacks A, B, and Rh antigens on the surface of the red blood cells, meaning it can be transfused into patients of any blood type without triggering an immune reaction.

8. Which cell organelle is known as the "powerhouse of the cell"?

A) Nucleus
B) Ribosome
C) Mitochondria
D) Golgi apparatus
Correct Answer: C) Mitochondria

Explanation: Mitochondria generate most of the chemical energy needed to power the cell's biochemical reactions, storing it in a molecule called ATP.

9. What is the common chemical name for baking soda?

A) Sodium Carbonate
B) Sodium Bicarbonate
C) Potassium Chloride
D) Calcium Carbonate
Correct Answer: B) Sodium Bicarbonate

Explanation: Baking soda is sodium bicarbonate ($NaHCO_3$). Sodium carbonate ($Na_2CO_3$) is commonly known as washing soda.

10. A "Light Year" is used as a unit to measure:

A) Time
B) Speed of light
C) Distance
D) Intensity of light
Correct Answer: C) Distance

Explanation: Despite the word "year," a light year measures distance. It is the distance that light travels in a vacuum in one Earth year (about 9.46 trillion kilometers).

11. What is the longest and strongest bone in the human body?

A) Tibia
B) Fibula
C) Femur
D) Humerus
Correct Answer: C) Femur

Explanation: The femur, or thigh bone, is the longest, heaviest, and strongest bone in the human body.

12. Malaria is transmitted to humans by the bite of an infected female Anopheles mosquito. The actual disease is caused by a:

A) Bacteria
B) Virus
C) Fungi
D) Protozoa
Correct Answer: D) Protozoa

Explanation: Malaria is caused by Plasmodium parasites, which are single-celled microorganisms classified as protozoa. The mosquito acts as a vector.

13. Which class of chemicals was primarily responsible for the depletion of the ozone layer?

A) Nitrogen oxides
B) Carbon monoxide
C) Chlorofluorocarbons (CFCs)
D) Methane
Correct Answer: C) Chlorofluorocarbons (CFCs)

Explanation: CFCs, once widely used in refrigerants and aerosols, rise into the stratosphere where UV radiation breaks them down, releasing chlorine atoms that destroy ozone molecules.

14. In the human body, the digestion of proteins primarily begins in the:

A) Mouth
B) Stomach
C) Small Intestine
D) Large Intestine
Correct Answer: B) Stomach

Explanation: While carbohydrate digestion begins in the mouth with saliva, protein digestion begins in the stomach through the action of hydrochloric acid and the enzyme pepsin.

15. Which is the hottest planet in our solar system?

A) Mercury
B) Venus
C) Mars
D) Jupiter
Correct Answer: B) Venus

Explanation: Although Mercury is closer to the Sun, Venus is the hottest planet due to a dense atmosphere of carbon dioxide that creates a runaway greenhouse effect, trapping heat.

16. The instrument used to measure the intensity of earthquakes is called a:

A) Barometer
B) Seismograph
C) Hygrometer
D) Anemometer
Correct Answer: B) Seismograph

Explanation: A seismograph (or seismometer) records the seismic waves caused by an earthquake. A barometer measures atmospheric pressure, a hygrometer measures humidity, and an anemometer measures wind speed.

17. Which component of the blood is primarily responsible for blood clotting?

A) Red blood cells
B) White blood cells
C) Platelets
D) Plasma
Correct Answer: C) Platelets

Explanation: Platelets (thrombocytes) are tiny blood cells that help your body form clots to stop bleeding. If a blood vessel is damaged, it sends out signals that platelets respond to by clumping together.

18. The image formed on the retina of the human eye is:

A) Real and upright
B) Virtual and inverted
C) Real and inverted
D) Virtual and upright
Correct Answer: C) Real and inverted

Explanation: The human eye has a convex lens which converges light rays to form a real, inverted image on the retina. The brain then processes this image so we perceive it as upright.

19. What is the primary gas that plants absorb from the atmosphere during photosynthesis?

A) Oxygen
B) Nitrogen
C) Carbon Dioxide
D) Carbon Monoxide
Correct Answer: C) Carbon Dioxide

Explanation: During photosynthesis, plants take in carbon dioxide ($CO_2$) and water ($H_2O$) from the air and soil. They use sunlight to transform these into glucose (food) and release oxygen as a byproduct.

20. Which element is a liquid at room temperature?

A) Sodium
B) Mercury
C) Calcium
D) Iron
Correct Answer: B) Mercury 

Explanation: Mercury is the only metal that is in a liquid state at standard room temperature and pressure. Bromine is the only non-metal liquid at room temperature.