Assertion (A) : Haloalkanes react with KCN to form alkyl cyanides as a main product while with $\mathrm{AgCN}$ form isocyanide as the main product.
Reason (R) : $\mathrm{KCN}$ and $\mathrm{AgCN}$ both are highly ionic compounds.
In the light of the above statements, choose the most appropriate answer from the options given below :
Identify A and B in the following reaction sequence.
The product (C) in the below mentioned reaction is :
$$\mathrm{CH}_3-\mathrm{CH}_2-\mathrm{CH}_2-\mathrm{Br} \xrightarrow[\Delta]{\mathrm{KOH}_{(\text {alc) }}} \mathrm{A} \xrightarrow{\mathrm{HBr}} \mathrm{B} \xrightarrow[\mathrm{KOH}_{(\mathrm{aq})}]{\Delta} \mathrm{C}$$
Given below are two statements:
Statement - I: High concentration of strong nucleophilic reagent with secondary alkyl halides which do not have bulky substituents will follow $$\mathrm{S}_{\mathrm{N}}{ }^2$$ mechanism.
Statement - II: A secondary alkyl halide when treated with a large excess of ethanol follows $$\mathrm{S}_{\mathrm{N}}{ }^1$$ mechanism.
In the light of the above statements, choose the most appropriate from the options given below: