Suppose a consumer purchases only two goods, X and Y, with her fixed income. She has the following utility function and income and faces these prices. U = X0.3 * Y0.7, PX = PY = 3, I = 60. What is the consumer's optimal consumption bundle?

a) 5 units of X, 10 units of Y
b) 10 units of X, 5 units of Y
c) 6 units of X, 8 units of Y
d) 8 units of X, 6 units of Y