The coldest layer of the atmosphere is:
a) Troposphere
b) Stratosphere
c) Mesosphere
d) Thermosphere
Answer: c) Mesosphere

Which of the following gases is responsible for the depletion of the ozone layer?
a) Carbon dioxide
b) Chlorofluorocarbons (CFCs)
c) Nitrogen
d) Argon
Answer: b) Chlorofluorocarbons (CFCs)

The greenhouse gas with the highest global warming potential is:
a) Carbon dioxide
b) Methane
c) Nitrous oxide
d) Chlorofluorocarbons (CFCs)
Answer: d) Chlorofluorocarbons (CFCs)

The main component of smog is:
a) Nitrogen
b) Oxygen
c) Ozone
d) Carbon monoxide
Answer: c) Ozone

Which process releases oxygen into the atmosphere?
a) Respiration
b) Photosynthesis
c) Combustion
d) Nitrogen fixation
Answer: b) Photosynthesis

What is the role of the ozone layer in the atmosphere?
a) To trap heat
b) To absorb ultraviolet radiation
c) To reflect sunlight
d) To produce oxygen
Answer: b) To absorb ultraviolet radiation

Which of the following gases is a primary greenhouse gas?
a) Nitrogen
b) Carbon dioxide
c) Argon
d) Neon
Answer: b) Carbon dioxide

The primary effect of acid rain is:
a) Global warming
b) Ozone depletion
c) Damage to aquatic ecosystems and vegetation
d) Increased ultraviolet radiation
Answer: c) Damage to aquatic ecosystems and vegetation

The term “ozone hole” refers to:
a) A region of intense ultraviolet radiation
b) A region of significantly reduced ozone concentration
c) A region of high carbon dioxide levels
d) A region of high sulfur dioxide levels
Answer: b) A region of significantly reduced ozone concentration

Which of the following is an effect of air pollution?
a) Increased agricultural productivity
b) Improved air quality
c) Respiratory health problems
d) Decreased acid rain
Answer: c) Respiratory health problems