Figure 21-10 A graph of Quantity of y versus Quantity of x shows a budget line, for convenience called Line 1, decreasing linearly, and 3 indifference curves, falling from left to right, I 0, I 1, and I 2, from left to right. Point A is marked on I 1. Point C is tangent to the budget line on I 1. Points B and D cross the budget line and are on I 0. Point E is on I 2 and is beyond the budget line. Refer to Figure 21-10 . It would be possible for the consumer to reach I 3 if a. the price of X increases. b. the price of Y decreases. c. income decreases. d. the price of Y increases