Which of the following reagents reacts with $but-1-ene$ to give an optically inactive product?

Suppose the following reaction sequence: $CH \equiv CH$ $\xrightarrow[\text{excess}]{NaNH_2 / \text{liq. } NH_3} A$ $\xrightarrow{2 CH_3 - I} B$ $\xrightarrow{H_2 / Pd - BaSO_4, \text{ quinoline}} C$ and $C$ $\xrightarrow{H_2 / Pd - BaSO_4, \text{ quinoline}}$ $\xrightarrow{NaNH_2 / \text{liq. } NH_3} D$. How are $C$ and $D$ related?

The major product of the following reaction is:

Two alkenes,$X$ ($91\%$ yield) and $Y$ ($9\%$ yield),are formed when the following compound is heated:
The structures of $X$ and $Y$,respectively,are:

What are the products obtained from the hydroboration-oxidation of propene and its hydration in the presence of dilute sulfuric acid,respectively?

The major product $[B]$ in the following sequence of reactions is
$CH_3-C(CH(CH_3)_2)=CH-CH_2CH_3$ $\xrightarrow[(i) B_2H_6]{(ii) H_2O_2, OH^{-}} [A]$ $\xrightarrow[\Delta]{dil. H_2SO_4} [B]$