JEE · NEET Previous Year Question

In acidic medium, $K_2{\text{Cr}}_2{O}_7$ shows oxidising action as represented in the half reaction
${\text{Cr}}_2{O}_7^{2-}+{\text{XH}}^{+}+{\text{Ye}}^{-}\to 2A+{\text{ZH}}_{2}O$ $X\text{,}Y\text{,}Z$ and $A$ are respectively are:

Topic: JEE PYQ

Answer: D. Full step-by-step solution below.