The equilibrium constant for the reaction $A + 2B \rightleftharpoons 2C$ is 40. The Equilibrium constant for the reaction $C \rightleftharpoons B + 1/2 A$ is

Question

(a) 1/40

(b)  $(1/40)^{1/2}$

(c) $(1/40)^2$

(d) 40