According to the Empirical Work on Managed Exchange Rates by Economists

According to the empirical work on managed exchange rates by economists Bordo and Schwartz,

A) purchasing power parity is totally ineffective in explaining changes in exchange rates.
B) the G-7 nations are actually maintaining fixed exchange rates instead of managed floating exchange rates.
C) the Canadian central bank is dictating to the other G-7 countries what the exchange rates of the major currencies will be.
D) actions of the G-7 nations cannot influence exchange rates in the long run.