Under a System of Flexible Exchange Rates, an Increase in Demand

Under a system of flexible exchange rates, an increase in demand for a nation's currency in the foreign exchange market will:

A) ​cause the nation's currency to appreciate.
B) ​make it more expensive for the nation to import goods.
C) ​cause the nation's balance on current account to shift toward a deficit.
D) ​make it less expensive for foreigners to buy the nation's goods.