Haloalkanes And Haloarenes

Identify the product ' B ' in the following sequence of recations.

\(\mathrm{CH}_3 \mathrm{Br} \xrightarrow{\mathrm{KCN}} \mathrm{~A} \xrightarrow{\mathrm{Na}_2 / \mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}} \mathrm{~B}\)