If, in retaliation for "unfair" trade practices, Congress imposes a 30 percent tariff on Japanese DVD recorders, but at the same time, U.S. demand for Japanese goods increases, then, in the long run, ________, everything else held constant.
选项：

A: the Japanese yen should appreciate relative to the U.S. dollar
B: the Japanese yen should depreciate relative to the U.S. dollar
C: there is no effect on the Japanese yen relative to the U.S. dollar
D: the Japanese yen could appreciate, depreciate or remain constant relative to the U.S. dollar