$$ \text {In the following series of reactions identify the major products } \mathrm{A} \& \mathrm{~B} \text { respectively } $$

Which among the following halides will generate the most stable carbocation in the nucleophilic substitution reaction?

The major product of the following reaction is:

The products A and B in the following reactions, respectively are

$\mathrm{A} \stackrel{\mathrm{Ag}-\mathrm{NO}_2}{\longleftrightarrow} \mathrm{CH}_3-\mathrm{CH}_2-\mathrm{CH}_2-\mathrm{Br} \xrightarrow{\mathrm{AgCN}} \mathrm{B}$