The idea behind the Laffer curve is that increases in tax rates do not increase tax revenues proportionately because they decrease the:（）

单项选择题Which of the following is included in the M2 measure of the money supply（）

A. savings deposits.
B. time deposits.
C. all of the above.

单项选择题Which school of thought holds that fiscal policy is most effective（）

A. the basic Keynesian model.
B. the Crowding-Out model.
C. New Classical economics.