Which of the Following Should an International Manager Keep in Mind

Which of the following should an international manager keep in mind about the constantly fluctuating exchange rates?

A) The prices the firm charges should be quoted in the firm's currency exclusively.
B) The firm and its customers should use the exchange rate as it stands on the date of each transaction, there is no scope for an agreement between them to use any other specific exchange rate.
C) If goods are bought from a supplier whose currency is appreciating against the buyer's currency, the buyer will have to pay a lesser amount of their currency to complete the purchase.
D) The time taken between placement and delivery of an order can at times go up to a few months; fluctuations in the exchange rate during that time can cost or earn the firm money.