When $CH_3CH_2CH_2CHCl_2$ is treated with $2 \ g$ equivalent of $NaNH_2$,the product formed is:

$CH_3-C \equiv CH \xrightarrow[(ii) H_2O_2/OH^{\Theta}]{(i) BH_3-THF} (P)$
$CH_3-C \equiv CH \xrightarrow[(ii) NaBH_4]{(i) Hg(OAc)_2/H_2O} (Q)$
Choose the correct option

An unsaturated hydrocarbon $X$ on ozonolysis gives $A$. Compound $A$ when warmed with ammoniacal silver nitrate forms a bright silver mirror along the sides of the test tube. The unsaturated hydrocarbon $X$ is ..... .

The synthesis of $3-$octyne is achieved by adding a bromoalkane into a mixture of sodium amide and an alkyne. The bromoalkane and alkyne respectively are

Which of the following compounds forms a $Na$-salt upon reaction with $NaNH_2$?

$CH \equiv CH + HBr \to X$,the product $X$ is: