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  9. Q40

UPPSC PCS 2018 · Question 40 of 142

Which of the following is the secondary pollutant?

Environment

  1. ASmogCorrect
  2. BCarbon dioxide
  3. CCarbon mono-oxide
  4. DFly ash

Answer: A. Smog

Explanation

Smog (photochemical) is a secondary pollutant formed by reactions of primary pollutants; the others are primary.

Source: https://www.onlyiasexam.com/2021/10/2018-uppsc-pre-solved-question-papers.html

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