Reaction of $R-CO-NH_2$ with a mixture of $Br_2$ and $KOH$ gives $R-NH_2$ as main product .The intermediate involved in the reaction are 1. $R-CO-NHBr$ 11 . $R-N =C=O$ 111. $R-NH-Br$ 1v. $H-CO-NBr_2$

Question

$\begin {array} {1 1} (A)\;All & \quad (B)\;1, 11 \\ (C)\;11, 1v & \quad (D)\;only\: 1v \end {array}$