Which of the following is true?

a) If banks are eager to lend (reserves are scarce) and the Fed increases the (minimum) reserve requirements, the federal funds rate will increase and the money supply will decrease.

b) All else equal, an exogenous decrease in money velocity will result in higher prices in the long run.

c) A significant decrease in deposit insurance coverage will lead to an increase in money supply.

d) An increase in the job finding rate will raise the natural rate of unemployment.