An orgnic compound (A) on reduction gave a compound (B). Upon treatment with `HNO_(2)` ,(B) gave ethyl alcohol and on warming with `CHCI_(3)`, and alcoholic KOH, (b) gave offensive smell. The compound (A) is:
A. `CH_(3)NH_(2)`
B. `CH_(3)NC`
C. `CH_(3)CN`
D. `C_(2)H_(5)CN`