\({\mathrm{C}}_{2}{\mathrm{H}}_{5}\mathrm{Br}\overset{\mathrm{Alc}\mathrm{KOH}}{\to }\mathrm{A}\overset{{\mathrm{Br}}_{2…

\({\mathrm{C}}_{2}{\mathrm{H}}_{5}\mathrm{Br}\overset{\mathrm{Alc}\mathrm{KOH}}{\to }\mathrm{A}\overset{{\mathrm{Br}}_{2}}{\underset{{\mathrm{CCl}}_{4}}{\to }}\mathrm{B}\overset{\mathrm{KCN}}{\underset{\mathrm{Excess}}{\to }}\mathrm{C}\overset{{\mathrm{H}}_{3}{\mathrm{O}}^{+}}{\underset{\mathrm{Excess}}{\to }}\mathrm{D}\)

Acid D formed in the above reaction is :

[JEE Main 2024, 1 Feb (Shift 2)]