U.S.income Tax Treaties

U.S.income tax treaties:

A) Provide for primary taxation with a tax credit for income sourced in one country and earned by a resident of the other treaty country.
B) Provide for taxation exclusively by the source country.
C) Provide that the country with the highest tax rate will be allowed exclusive tax collection.
D) Provide for taxation exclusively by the country of residence.
E) None of the above.