Answer the question on basis of passage given below :
Molecular nitrogen is very little reactive chemically. During lightning discharge, atmospheric nitrogen and oxygen combines to form nitric oxide which also combines with oxygen to form nitrogen dioxide. Both NO and \(NO _2\) constitute smog which is very poisonous. It can cause burning sensation in the eyes and adversely affect respiratory system.
What are the constituents of photo chemical smog ?

1. A Photochemical smog are oxide of nitrogen, organic compounds like formaldehyde acrolein and peroxyacetyl nitrate (PAN).
2. B Photochemical smog are oxide of nitrogen, organic compounds like formalin, acrolein and PAN.
3. C Photochemical smog are oxide of sulphur, organic compounds like formalin, acrolein and PAN.
4. D Photochemical smog are oxide of sulphur, organic compounds like formaldehyde, acrolein and PAN.