$1$-butyne can be distinguished from $2$-butyne by

In order to complete the reaction $1-Pentyne$ $\xrightarrow{a} 4-Octyne$ $\xrightarrow{b} cis-4-Octene$,$a$ and $b$ will be:
$A) NaNH_2; CH_3CH_2CH_2Br : H_2, (1 \ mole) \text{ Lindlar catalyst}$
$B) NaNH_2; CH_3CH_2CH_2Br : H_2, (2 \ moles) \text{ Pd or Ni}$
$C) NaNH_2; CH_3CH_2CH_2Br : H_2, (1 \ mole) \text{ Pd or Ni}$
$D) NaNH_2; CH_3CH_2CH_2Br : BH_3, H_2O_2, OH^-$

$1-$Butyne can be distinguished most easily from $2-$butyne by

The major product obtained from the following reaction is

The reagent for the reaction $R-CH_2-CCl_2-R \xrightarrow{\text{reagent}} R-C \equiv C-R$ is:

Hydrogenation of $2-$Butyne in the presence of Lindlar's catalyst gives