Which of the Following Does NOT Explain Why the Supply

Which of the following does NOT explain why the supply of foreign exchange to Canada is generated by the desire of foreigners to acquire U.S.dollars?  

A)  because Canada is considered a safe haven in times of political unrest 
B)  because the U.S. dollar has long been accepted as an international medium of exchange 
C)  because foreigners want to buy Canadian assets 
D)  because Canadian goods have become less attractive to foreigners