$$C{H_3} - C{H_2} - CN\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Ether}^{C{H_3}MgBr}} A\buildrel {{H_3}{O^ + }} \over \longrightarrow B\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{HCl}^{Zn - Hg}} C$$

The correct structure of C is

Most stable product of the following reaction is:

Two isomers (A) and (B) with Molar mass 184 g/mol and elemental composition C, 52.2%; H, 4.9% and Br 42.9% gave benzoic acid and p-bromobenzoic acid, respectively on oxidation with KMnO₄. Isomer 'A' is optically active and gives a pale yellow precipitate when warmed with alcoholic AgNO₃. Isomer 'A' and 'B' are, respectively

Consider the above reactions, the product A and product B respectively are