The $pK_q$ values of four carboxylic acid are 4.76, 4.19, 0.23 and 3.41 respectively. The $pK_a$ value of strongest carboxylic acid among them is :

Question

$\begin {array} {1 1} (1)\;4.19 & \quad (2)\;3.41 \\ (3)\;0.23 & \quad (4)\;4.76 \end {array}$