Answer:
d. benefit; strengthens
Explanation: Exchange rate is a term used in the currency market or in an economy to describe the value of a given currency against another currency, the exchange rate is usually used in most cases against a generally accepted reference currency such as the United States of America Dollar. WHEN THE EXCHANGE RATE OF A CURRENCY INCREASES(STRENTHENS) THE VALUE OF THE CURRENCY INCREASES WHICH HELPS THE USERS OF THE CURRENCY TO BENEFIT FROM THE INCREASED VALUE.