问题
单项选择题
Supply-side economics focuses on the impact of:（）
A. government borrowing on interest rates and private consumption and investment.
B. higher government spending and lower taxes on aggregate demand.
C. axes on the incentive to engage in productive activities.
答案
参考答案：C
解析：
The effect of taxes on the incentive to engage in productive activities and thus on aggregate supply is the focus of supply-side economics.