Determine the order of basic strength for the following compounds:

The correct statements about the products $B$ and $C$ in the given reactions are
$CH_3CH_2OH$ $\xrightarrow[\text{Anhy } ZnCl_2]{HCl} A$ $\xrightarrow[\text{AgCN}]{\text{ethanolic}} \underset{\text{Minor}}{B} + \underset{\text{Major}}{C}$
$I$. $B$ and $C$ are functional isomers
$II$. With $H_2 / \text{Catalyst}$,$B$ gives $1^{\circ}$ amine and $C$ gives $2^{\circ}$ amine
$III$. $B$ on acid hydrolysis gives formic acid and $C$ gives $C_3H_6O_2$
$IV$. $C$ forms isocyanate with $HgO$

Amongst the following,the most basic compound is:

The missing reagent is:

Identify the strongest base from the following.

In the reaction sequence $CH_3Cl$ $\xrightarrow{KCN}$ $\xrightarrow{+4H} A$ $\xrightarrow{NaNO_2/HCl} \text{Ethyl alcohol} + ?$. What are the major and minor products formed?