The correct answer is Nitrogen Dioxide, Ozone, and peroxyacetyl nitrate in the presence of sunlight.

Nitrogen Dioxide Released mainly from vehicle exhaust and industrial emissions.

Sunlight Sunlight's energy initiates the chemical reactions that form smog.

Volatile Organic Compounds These are released from gasoline, paints, solvents, and other sources. They react with NO2 in the presence of sunlight.

Ozone Ground-level ozone is a major component of photochemical smog, created by the reactions between NO2 and VOCs. Peroxyacetyl Nitrate (PAN) PAN is another harmful component of smog, formed in the same reactions.

The simplified process Sunlight triggers reactions between Nitrogen Dioxide and VOCs, leading to the formation of ozone, PAN, and other noxious components of photochemical smog.