If the U.S. and Japan engage in substantial financial flows but little trade, ____ directly influences their exchange rate the most. If the U.S. and Switzerland engage in much trade but little financial flows, ____ directly influences their exchange rate the most.
a. interest rate differentials; interest rate differentials
b. inflation and interest rate differentials; interest rate differentials
c. income and interest rate differentials; inflation differentials
d. interest rate differentials; inflation and income differentials
e. inflation and income differentials; interest rate differentials