Which is the major product of the following reaction?

Match the reactant in Column-$I$ with the reaction in Column-$II$:

Column-$I$	Column-$II$
$(i)$ Acetic acid	$(a)$ Stephen
$(ii)$ Sodium phenate	$(b)$ Friedel-Crafts
$(iii)$ Methyl cyanide	$(c)$ $HVZ$
$(iv)$ Toluene	$(d)$ Kolbe's

Which of the following best describes the nucleophilic addition step in the acid-catalyzed hydrolysis of acetonitrile $(CH_3CN)$?

Identify the correct option based on the following reaction sequence:
Acetic anhydride $\xrightarrow[(ii) EtOH/H^+/\Delta]{(i) H_3O^+} (A)$ $\xrightarrow[(ii) H_3O^+/\Delta]{(i) NaOEt} (B)$

Among formic acid,acetic acid,propanoic acid and phenol,the strongest acid in water is

Which of the following represents the decreasing order of reactivity towards reaction with ammonia?