(c)
$CH_{3}CH_{2}COOH\overset{\ \ \ \ NH_{3}\ \ \ \ \ }{\rightarrow}CH_{3}CH_{2}CONH_{2}$
Propionic acid propionamide
(X)
$\overset{Br_{2} + KOH\ \ \ \ }{\rightarrow}CH_{3}CH_{2}NH_{2}\overset{HNO_{2}\ \ \ }{\rightarrow}CH_{3}CH_{2}OH$
Ethyl amine ethyl alcohol
(Y) (Z)