4. Assume that good x is on the horizontal axis and goody is on the vertical axis, and that preferences are complete, transitive, monotonic and convex. Suppose the price consumption curve as the price of x changes is a horizontal line and consider the truthfulness of the following statements. I. Good y's Engel curve must be upward sloping. II. The income consumption curve must be upward sloping. a. Only statement I is true. b. Only statement II is true. 0. Both statements I and II are true. (1. Neither statement is true