Explain how policy coordination among countries in a fixed-exchange-rate system can increase the degree to which monetary policy may be used to pursue macroeconomic goals. A. If countries use expansionary fiscal policy at the same time, then the currencies won't become overvalued or undervalued relative to each other. B. If countries use expansionary monetary policy at the same time, then the currencies won't become overvalued or undervalued relative to each other. C. If one country uses expansionary monetary policy and the other uses contractionary monetary policy, then the currencies won't become overvalued or undervalued relative to each other. D. If one country uses expansionary fiscal policy and the other uses contractionary fiscal policy, then the currencies won't become overvalued or undervalued relative to each other