Suppose an Economy with Two Goods (Candy and Desk)and Two

Suppose an economy with two goods (candy and desk) and two identical agents that is in a competitive equilibrium.The marginal cost of a piece of candy is given by MC_c = 4Q_c and the marginal cost of a desk is MC_d = 2 + Q_d.The current production level of candy (Q_c) is 4 pieces and of desks (Q_d) is 30.What can be said about the marginal utility of candy (MU_c) and the Marginal utility of desks (MU_d) ?

A) 3*MU_c = MU_d
B) MU_c = 0.5*MU_d
C) MU_c = MU_d = 4
D) MU_c = 2*MU_d