Which one of the following is not a constituent of photochemical smog?

AOzone (O3)

BPeroxyacetyl nitrate (PAN)

CDioxins ✓ Correct

DFormaldehyde (HCHO)

Correct answer: (C) Dioxins

Explanation

Dioxins come from burning chlorinated waste and are not part of photochemical smog.

Ozone is a key product of photochemical smog.

Peroxyacetyl nitrate is a characteristic component of photochemical smog.

Formaldehyde is among the aldehydes formed in photochemical smog.

The combustion by-product unrelated to sunlight-driven reactions is the odd one out.

Photochemical smog forms when sunlight acts on nitrogen oxides and hydrocarbons.

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