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

The major product obtained in the reaction of aniline with acetic anhydride is

Which of the following is the strongest base?

Given below are two statements:
Statement-$I$: In Hofmann degradation reaction,the migration of only an alkyl group takes place from carbonyl carbon of the amide to the nitrogen atom.
Statement-$II$: The group is migrated in Hofmann degradation reaction to an electron-deficient nitrogen atom.
In the light of the above statements,choose the most appropriate answer from the options given below:

Which of the following is the strongest base?

The correct order of basicity for the following molecules is $:$