(a)
Only ethyl acetate undergoes reduction with $LiAlH_{4}$ to give only ethyl alcohol, other esters given in option on reduction gives a mixture of alcohols.
$CH_{3}COOCH_{2}CH_{3} + 2H_{2}\underset{ether}{\overset{\ \ \ LiAlH_{4}\ \ \ }{\rightarrow}}2CH_{3}CH_{2}OH$