Which of the Following Should Be Subtracted While Calculating Aggregate

Multiple Choice

Which of the following should be subtracted while calculating aggregate demand of the U.S.?

A) Pakistan's purchase of F-16s from the U.S.
B) Computers imported by China from the U.S.
C) Memorabilia purchases in the U.S.by a foreign tourist.
D) A U.S.firm's purchase of German machinery.