Solved UPSC CDS/OTA Question
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Q · Basic Ecology and EnvironmentMedium · 45s
Which pollutant is mainly responsible for photochemical smog?
TopicBasic Ecology and Environment
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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NOₓ and hydrocarbons under sunlight form photochemical smog.
Final Answer: Option B — Nitrogen oxides