For main industrial countries such as Japan and the U.S.

a. it is hard to tell whether month-to-month variability of the exchange rate is similar to changes in price levels b. there is much more month-to-month variability of the exchange rate, suggesting that price levels are relatively sticky in the long run c. there is much more month-to-month variability of the exchange rate, suggesting that price levels are relatively sticky in the short run d. there is much less month-to-month variability of the exchange rate, suggesting that price levels are relatively sticky in the short run e. there is almost the same month-to-month variability of the exchange rate and price levels f. none of the above