Exhibit 1A-8 Straight line relationship 20 Price per 15 pizza (dollars) 10 5 0 10 20 30 40 Quantity of pizzas purchased (hundreds per week) Which of the following would cause a shift in the relationship shown in Exhibit 1A-8? O a. A fall in the quantity of pizza that people wish to purchase. O b. A rise in the price of pizza. O c. A fall in the price of pizza. O d. A fall in household incomes. O Icon Key