The difference between a forward exchange rate and a future spot exchange rate is

A. a forward exchange rate can be renegotiated if the parties agree, but a future spot exchange rate is fixed now to be applied to a future transaction at a specified future date.

B. very small, because a forward exchange rate is almost the same as a future spot exchange rate.

C. a forward exchange rate is fixed now to be used at a specific future date, but a future spot exchange rate is whatever exchange rate exists on the specific future date.

D. a forward exchange rate can change as the specified date approaches, but the spot rate is fixed now to be used at the specified future date and does not change.