Home PYQs UPPSC UPPSC MCQs Prelims 2019 (GS Paper I)

Question

Smog is essentially caused by the atmospheric presence of:

  1. Oxygen and ozone
  2. Ozone and nitrogen
  3. Oxygen and nitrogen
  4. Oxide of nitrogen and sulphur

Answer:

Option D: Oxide of nitrogen and sulphur

Detailed Solution:

The correct answer is “Oxide of nitrogen and sulphur”.

Smog (धुंध) is primarily caused by the atmospheric presence of oxides of nitrogen and sulfur. These pollutants, along with particulate matter and volatile organic compounds, contribute to the formation of smog, especially in urban areas.