Assertion (A): `Sb^(3+)` is not precipitated as sulphide when `H_(2)S (g)` is passed in alkaline solution.
Reason (R) : `[S^(2-)]` ion in basic medium is inadequate for precipitation.

Answer

C

Explanation

Sb(III) is a basic radical of IIB group of which group reagent is `H_(2)S` in presence of dilute HCl. It is necessary to maintain the proper hydrogen ion concentration for the precipitation of IV group cations.