Assuming Flexible Exchange Rates,which of the Following Would Result in an Increase

Multiple Choice

Assuming flexible exchange rates,which of the following would result in an increase in a country's exchange rate?

A) The purchase by the central bank of its own currency.
B) The purchase by the central bank of foreign currencies.
C) The sale by the central bank of its own currencies.
D) The central bank decreasing the country's interest rates.
E) The government imposing an export tax.