Suppose that a consumer is currently spending all of her income on 10 units of goods A and 5 units of goods on B. The price of A is $4.00 per unit, the price of good B is $10.00 per unit, the marginal utility of the last unit of good A consumed is 20, and the marginal utility of the last unit of good B consumed is 60. If the consumer wants to maximize her utility from consuming the two goods, she should __________.
a. consume more of good B and less of good A
b. consume more of good A and less of good B
c. continue to consume 10 units of goods A and 5 of good B
d. consume more of both goods