# An organic compound A upon reacting with $NH_3$ gives B. On heating B gives C. C in presence of KOH reacts with $Br_2$ to give $CH_3CH_2NH_2$. A is
( B ) $CH_3CH_2COOH$
( C ) $CH_3CH_2CH_2COOH$
( D ) $CH_3COOH$