Suppose That MU_x = 10 and MU_y = 20

Suppose that MU_x = 10 and MU_y = 20.Further suppose that the consumer's budget constraint can be expressed as 20x + 10y = 400.For this consumer,the optimal amount of good to buy would be

A) 5.
B) 0.
C) 20.
D) 40.