Identify the final product $C$ in the following sequence.

$$ \begin{aligned} \mathrm{CH}_3 \mathrm{CH}_2 \mathrm{Br}+(\text { alc. } \mathrm{KOH}) & \xrightarrow{h \nu} A+\mathrm{Br}_2 \longrightarrow B+(\text { alc. } \mathrm{KCN}) \longrightarrow C \end{aligned} $$

Identify the product $C$ in the following given reaction?

$$\mathrm{C}_2 \mathrm{H}_5 \mathrm{I} \xrightarrow{\mathrm{KOH}} A \xrightarrow{\mathrm{Br}_2} B \xrightarrow{\mathrm{KCN}} C$$

Which one of the following compounds is formed in the laboratory from benzene by a substitution reaction?

In the given reaction,

The product P is