A) 12%
B) 18%
C) 21%
D) 25%
Answer: C) 21%
Author: Shumaim Naeem
Which chemical is responsible for ozone layer depletion?
A) Carbon dioxide
B) Methane
C) Chlorofluorocarbons (CFCs)
D) Nitrogen oxides
Answer: C) CFCs
In nuclear reactors, which material is commonly used as a moderator?
A) Graphite
B) Boron
C) Cadmium
D) Lead
Answer: A) Graphite
The chemical used to preserve biological specimens is:
A) Formaldehyde
B) Chloroform
C) Acetone
D) Benzene
Answer: A) Formaldehyde
Which vitamin is essential for the synthesis of clotting factors in liver?
A) Vitamin A
B) Vitamin D
C) Vitamin E
D) Vitamin K
Answer: D) Vitamin K
The unit of electric resistance is:
A) Watt
B) Coulomb
C) Ohm
D) Volt
Answer: C) Ohm
Which blood component helps in clotting?
A) Plasma
B) Red blood cells
C) White blood cells
D) Platelets
Answer: D) Platelets
Which part of the electromagnetic spectrum has the shortest wavelength?
A) Gamma rays
B) X-rays
C) Ultraviolet rays
D) Infrared rays
Answer: A) Gamma rays
The most abundant greenhouse gas naturally present in the Earth’s atmosphere is:
A) Carbon dioxide
B) Methane
C) Nitrous oxide
D) Water vapor
Answer: D) Water vapor
Which organelle contains its own DNA and ribosomes apart from the nucleus?
A) Lysosome
B) Mitochondria
C) Golgi apparatus
D) Endoplasmic reticulum
Answer: B) Mitochondria