Solved UPSC CDS/OTA Question
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Q · Environmental PollutionMedium · 45s
The term “Brown Air” is used for which type of smog?
TopicEnvironmental Pollution
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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Photochemical smog, common in cities like Los Angeles, appears brownish due to NO₂.
Final Answer: Option C — Photochemical smog