Which among the following reactions is used for the preparation of alkyl fluorides?

Identify ' B ' in the following conversion.

$$\mathrm{CH}_3-\mathrm{I} \xrightarrow{\mathrm{KCN}} \mathrm{~A} \xrightarrow{\mathrm{Na} / \mathrm{C}_2 \mathrm{H}_5 \mathrm{OH}} \mathrm{~B}$$

Which among the following is NOT allylic halide?

The correct order of reactivity for reactions involving cleavage of $\mathrm{C}-\mathrm{Cl}$ bond in following compounds is