A first row transition metal (M) does not liberate $$H_{2}$$ gas from dilute HCI. 1 mol of aqueous solution of $$MSO_{4}$$ is treated with excess of aqueous KCN and then $$H_{2} S(g)$$ is passed through the solution. The amount of MS (metal sulphide) formed from the above reaction is _______ mol.

A

3

B

1

C

0

D

2