Explanation

(d)
$H_{2}O,\ ROH,\ R - COOH$ etc are protic solvents because they are polar in nature and contain a hydrogen directly bonded to oxygen while other are aprotic solvents as they do not have a hydrogen bonded directly to oxygen. They are especially favourable for $S_{N}1$ reactions. While aprotic solvents cannot have hydrogen bond to the nucleophile because they does not have hydrogen bonded to nitrogen or oxygen. They are favourable for $S_{N}2$ reactions.