Identify compounds A,B and C in the following sequence of reactions.
`CH_3CH_2Ioverset(NaCN)(to)A underset(" Partial hydrolysis ")overset(OH^-)(to)B overset(NaOH+Br_2)(to)C`

Explanation

`underset("iodide)")underset("(Ethyl")(CH_(3)CH_(2)I)overset(NaCN)underset(-NaI)rarrunderset("(A)")underset("cyanide)")underset("(Ethyl")(CH_(3)CH_(2)CN)underset(underset("hydrolysis)")("(Partial"))overset(OH^(-))rarrunderset("(B)")underset("(Acetamide)")(CH_(3)-CONH_(2))overset(NaOH+Br_(2))underset(underset(underset("reaction)")("bromamide"))"(Hofmann")rarrunderset("(C)")underset("(Methylamine)")(CH_(3)NH_(2))`