Acetylene is obtained by the electrolysis of

The major product of the following reaction is: $CH_3-CH_2-CH(Br)-CH_2-Br \xrightarrow[(ii) NaNH_2 \text{ in liq. } NH_3]{(i) KOH \text{ alc.}}$

Consider the following transformations of a compound $P$ $(C_9H_{12})$:
$(i)$ $P \xrightarrow{NaNH_2, C_6H_5COCH_3, H_3O^+/\Delta} R$ (Optically active)
(ii) $P \xrightarrow{Pt/H_2} \text{propylcyclohexane}$
(iii) $P \xrightarrow{X, KMnO_4/H_2SO_4/\Delta} Q$ ($C_8H_{12}O_6$,Optically active acid)
Choose the correct option$(s)$:
$(A)$ $P$ is $3-$cyclohexylprop$-1-$yne
$(B)$ $X$ is $Pd-C/\text{quinoline}/H_2$
$(C)$ $P$ is $1-$cyclohexylprop$-2-$yne
$(D)$ $R$ is $1-$cyclohexyl$-4-$phenylbut$-3-$yn$-2-$ol

Which reaction converts $2$-hexyne into $trans$-$2$-hexene?

The major product in the following reaction is $H_3C-C\equiv CH + HBr$ (excess)

$C_6H_5-C \equiv C-CH_3 \xrightarrow[H_2SO_4]{HgSO_4, H_2O} A$. The major product $(A)$ is: