The reaction of a primary amine with an aldehyde gives $......$.

Which among the following amines has the lowest $pK_{b}$ value?

The number of compounds from the following which can undergo reaction with $Br_2/KOH$ (alcoholic) to give respective products, and these respective products can also be obtained separately by the Gabriel phthalimide synthesis, is:

Identify $'X'$ in the following sequence of reaction:
$C_6H_5N_2^+Cl^-$ $\xrightarrow{CuCN/KCN} P$ $\xrightarrow{LiAlH_4} Q$ $\xrightarrow{HNO_2} X$

In the reaction shown below,the major product$(s)$ formed is/are:

Aniline reacts with which of these to form a Schiff base?