Which of the following sulphides when dissolved in cone. ${\mathrm{HNO}}_3$ will show positive test with ammonium molybdate?

It is a sign that there are ${\mathrm{As}}^{3+}$ ions present when group- II precipitate dissolves in yellow ammonium sulphide and the colour of the solution is yellow. A yellow precipitate of arsenic (V) sulphide (C) is created when ammonium thioarsenide (B), which was formed when  ${\mathrm{As}}_2{\mathrm{S}}_3$ (A) was dissolved, decomposes with dilute HCl and dissolves in concentrated nitric acid on heating because of the generation of asenic acid. A canary yellow precipitate (D) is produced after heating the reaction mixture with ammonium molybdate solution. This demonstrates that ${\mathrm{As}}^{3+}$ ions are present.

The correct option is C ${\mathrm{As}}_2{\mathrm{S}}_3$