Because of Shifts in Preferences for Domestic or Foreign Goods

Because of shifts in preferences for domestic or foreign goods and because of the existence of trade barriers

A) purchasing power parity's underlying assumption is not valid.
B) the nominal exchange rate will fluctuate, but the real exchange rate will not.
C) purchasing power parity will be accurate in predicting short-run fluctuations in exchange rates, but not in predicting long-run fluctuations.
D) most national governments believe exchange rates should not be set by the market.