Photochemical smog is formed :
When Ultraviolet light from the sun reacts with nitrogen oxide in the atmosphere
When Ultraviolet light from the sun reacts with carbon monoxide in the atmosphere
When Ultraviolet light from the sun reacts with carbon dioxide in the atmosphere
All of the above
Photochemical smog is a type of smog produced when ultraviolet light from the sun reacts with nitrogen oxide in the atmosphere.