Prices of hamburgers (assume that this is an inferior good) have increased steadily in recent years. Over this same period, prices for ground chuck beef have increased and consumer incomes have decreased (notice these two events are happening at the same time). Which of the following best explains the rising prices of hamburgers?

Justify your answer with a diagram of supply and demand (show the shift of the curves). There is no need to show a graph for each part a-d), only for the answer of your choice.

a) The supply curve for hamburgers has shifted to the right while the demand curve for hamburgers has shifted to the left. b) The demand curve for hamburgers has shifted to the right while the supply curve has shifted to the left. c) The demand curve and the supply curve for hamburgers have both shifted to the right. d) The demand curve and the supply curve for hamburgers have both shifted to the lef