Which of the following is a reason why the aggregate demand curve slopes downward? a. At a higher price level, fewer goods and services are available. b. Periods when the price level is rising are usually time of shift declined in economic activity. c. Households feel poorer with an increase in average prices. d. If the U.S. price level rises, foreigners will buy more U.S. goods, leaving fewer U.S. goods for domestic consumer's e. As the price level rises, business leaders become pessimistic about the future and reduce production.