Solved UPSC CDS/OTA Question
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Q · Environmental PollutionMedium · 45s
Which of the following is/are considered primary pollutants? 1. Carbon monoxide 2. Sulphur dioxide 3. Ozone
TopicEnvironmental Pollution
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Q 1 / 30Next question →
Step-by-Step Solution
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Primary pollutants are emitted directly from a source. CO and SO₂ are directly emitted by combustion processes. Ozone is a secondary pollutant formed by photochemical reactions involving primary pollutants like NOx and VOCs.
Final Answer: Option B — 1 and 2 only