$2-$pentyne on reaction with sodium in liquid ammonia produces compound $A$. What is $A$?

What is obtained when $N_2$ reacts with calcium carbide?

The poisonous gas 'Lewisite' is obtained by the reaction of:

$A \xrightarrow{Ag_2O} \text{ppt}$
$A$ $\xrightarrow{Hg^{2+} / H^{+}} B$ $\xrightarrow{NaBH_4} C$ $\xrightarrow{conc. HCl / ZnCl_2} \text{Turbidity within 5 minutes}$.
Consider the following reactions,'$A$' is:

The reaction $Ph-C \equiv CH \xrightarrow[{(2)\,H_2O_2/OH^{-}}]{{(1)\,BH_3.THF}}$ Product; the product is

Which of the following does not react with acetylene?