Some reactions of $NO _2$ relevant to photochemical smog formation are

Identify $A , B , X$ and $Y$
Given below are two statements:
Statement I: Transfer RNAs and ribosomal RNA do not interact with mRNA.
Statement II: RNA interference (RNAi) takes place in all eukaryotic organisms as a method of cellular defence.
In the light of the above statements, choose the most appropriate answer from the options given below:
There is a number of factors that contribute to the pollution of the environment. Some of the major causes of atmospheric pollution are given below -