Aspirin is acetyl salicylic acid; the pair of functional groups present in the compound is :

Question

$\begin {array} {1 1} (1)\;Hydroxyl\: ester & \quad (2)\;Carboxylic\: acid\: hydroxyl \\ (3)\;Carboxylic\: acid\: keto & \quad (4)\;Carboxylic\: acid\: ester \end {array}$