SiyangWu

B) is a necessary assumption. If you negate B), the conclusion of the

passage will fall apart.

A) and C) on the other hand, are not necessary for the argument to

hold. If you negate either, the conclusion still holds.

A) is more like an inference, not necessarily true.

C) is even worse. If C) is true, then Japan and Europe would buy more

paper pulps from U.S. without a change in the value of U.S. dollars.