Immune defense means that the body can () A: resist to invasion of pathogens and neutralize their toxic products B: exclude the aging and injuried cells and keep the balance of inner<br/>environment C: surveil and clear transformed cells inside the body D: present unresponsive state to antigenic foreign substances E: present unresponsive state to self antigenic

Which of the following statements is accurate?____. A: Fiscal policy is not effective with fixed exchange rates in an environment of highly responsive international capital flows. B: Fiscal policy is highly effective with fixed exchange rates and unresponsive international capital flows. C: Fixed exchange rates greatly constrain a country's ability to pursue an independent monetary policy. D: Contractionary monetary policy is effective under a fixed exchange rate regime.

Which of the following statements is accurate? ____. A: Fiscal policy is not effective with fixed exchange rates in an<br/>environment of highly responsive international capital flows. B: Fiscal policy is highly effective with fixed exchange rates and<br/>unresponsive international capital flows. C: Fixed exchange rates greatly constrain a country's ability to pursue<br/>an independent monetary policy. D: Contractionary monetary policy is effective under a fixed<br/>exchange-rate regime.