Explanation

(d)
When an alkyl halide reacts with alcoholic ammonia in a sealed tube then a mixture of primary, secondary and tertiary amine is formed.
$RX\ \ + \ \ NH_{3}\ \rightarrow \ \ RNH_{2}\ \ + \ \ HX$
$\ pri$-amine
$RNH_{2}\ \ + \ \ XR\ \ \rightarrow \ \ R_{2}NH\ \ + \ \ HX$
$\sec$-amine
$R_{2}NH\ \ + \ \ HX\ \ \rightarrow \ \ R_{3}N\ \ + \ \ HX$
$ter$-amine