Which of the following is the strongest base?

Given below are two statements:
Statement $I$: Aniline does not undergo Friedel-Crafts alkylation reaction.
Statement $II$: Aniline cannot be prepared through Gabriel synthesis.
In the light of the above statements,choose the correct answer from the options given below:

For the following diazonium ions,the order of reactivity towards diazo-coupling with phenol in the presence of dilute $NaOH$ is:
$(I)$ $p-Me_2N-C_6H_4-N_2^+$
$(II)$ $p-O_2N-C_6H_4-N_2^+$
$(III)$ $p-CH_3O-C_6H_4-N_2^+$
$(IV)$ $p-CH_3-C_6H_4-N_2^+$

Find $A$ in the reaction $R-NH_2 + A \longrightarrow$ Schiff base.

For reaction-$I$,the reagents are $CH_3CONH_2, KOH, Br_2$. For reaction-$II$,the reagents are $CH_3NH_2, CHCl_3, KOH$. What are the intermediates for reaction-$I$ and reaction-$II$ respectively?

$A$ primary amine can be converted to an alcohol by the action of