A is corrent. The direct quotation is the rate expressed in US dollars. It means that $.90 can be exchanged for 1 Canadian dollar. The direct quotation is $.90/1. The indirect quotation is the inverse of the direct quotation or 1/$.90.
B is incorrect. The direct quotation is the rate expressed in US dollars. It means that $.90 can be exchanged for 1 Canadian dollar. The direct quotation is $.90/1. The indirect quotation is the inverse of the direct quotation or 1/$.90.
C is incorrect. The fraction $.90/1 expresses the direct exchange rate. It means that $.90 can be exchanged for 1 Canadian dollar.
D is incorrect. The direct quotation is the rate expressed in US dollars. It means that $.90 can be exchanged for 1 Canadian dollar. The direct quotation is $.90/1. The indirect quotation is the inverse of the direct quotation or 1/$.90.
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