The isomeric deuterated bromide with molecular formula $$\mathrm{C_4H_8DBr}$$ having two chiral carbon atoms is

The compound which will have the lowest rate towards nucleophilic aromatic substitution on treatment with OH$$^-$$ is

Assertion A : Hydrolysis of an alkyl chloride is a slow reaction but in the presence of NaI, the rate of the hydrolysis increases.

Reason R : I$$^{-}$$ is a good nucleophile as well as a good leaving group.

In the light of the above statements, choose the correct answer from the options given below

Compound 'A' undergoes following sequence of reactions to give compound 'B'.

The correct structure and chirality of compound 'B' is

[where Et is $$\left.-\mathrm{C}_{2} \mathrm{H}_{5}\right]$$