question_answer

In Delhi between 1997 and 2005 a substantial fall has been found in

A)  \[C{{O}_{2}}\] and \[S{{O}_{2}}\]          

B)  \[C{{O}_{2}}\] and \[CO\]

C)  \[S{{O}_{2}}\]and \[N{{O}_{2}}\]           

D)  \[CO\] and \[N{{O}_{2}}\]