Which of the following compounds reacts with ammonia to form urotropine?

Which of the following is a nucleophilic addition reaction?

$CH_3CH=CHCHO$ $\xrightarrow[\text{Aldol condensation}]{OH^{-}}$ $\xrightarrow{\Delta} A$; Product $A$ is

An organic compound $CH_3-CH=CH-CH_2-CHO$ is taken in two different containers $A$ and $B$. Sample in $A$ is treated with $H_2 / Ni$ forming new compound $P$. Sample in $B$ is treated with $LiAlH_4$ and hydrolyzed further forming new compound $Q$. Identify $P$ and $Q$.

The following transformation can be best carried out using:

Which one of the following aldehydes will not form an aldol when treated with $dil. \, NaOH$?