Which of the following statements is true about supply-side economics?

• A. The main change made by the tax laws of 1981 and 1986 was to increase marginal tax rates in order to balance the budget
• B. The Laffer Curve says that, if marginal tax rates fall, tax revenues will rise, and the budget deficit will decrease
• C. If the tax laws of 1981 and 1986 had had their intended effect, consumption would have risen, causing an increase in both real GDP and in the price level
• D. All of these