The use of money and credit controls to influence macroeconomics
activity is known as?
a- Keynes Theory
b- Classical Theory
C- Monetary Policy
D- Supply-Side Policy

C - monetary policy

Def. - http://www.investorwords.com/cgi-bin/getword.cgi?3097

"The regulation of the money supply and interest rates by a central
bank, such as the Federal Reserve Board in the U.S., in order to
control inflation and stabilize currency. Monetary policy is one the
two ways the government can impact the economy. By impacting the
effective cost of money, the Federal Reserve can affect the amount of
money that is spent by consumers and businesses."

C- Monetary Policy

"2. Monetary policy – The use of money and credit controls to
influence macroeconomic activity" 
http://garnet.acns.fsu.edu/~fdv3471/intro11.html