Hydroboration-oxidation and acidic hydration will not give the same products in case of
An organic compound ′A′(C3H4) on hydration in presence of H2SO4/HgSO4 gives white crystalline product (D) with sodium hydrogensulphite. It gives negative Tollen's test and positive iodoforn's test. On drastic oxidation ′B′ gives compound ′C′(C2H4O2) along with formic acid. Identify compounds ′A′,′B′ and ′C′ and explain all the reactions.