In the above chemical reaction sequence "A" and "B" respectively are:

A

$$H_2O, H^+$$ and $$KMnO_4$$

B

$$O_3, Zn/H_2O$$ and $$NaOH_{(alc)}/I_2$$

C

$$O_3, Zn/H_2O$$ and $$KMnO_4$$

D

$$H_2O, H^+$$ and $$NaOH_{(alc)}/I_2$$