Which of the Following Is Unique to Export-Import Brokers, Differentiating

Which of the following is unique to export-import brokers, differentiating them from general brokers?

A) They usually have a temporary relationship with the buyer and seller while a particular deal is negotiated.
B) They specialize in bringing together buyers and sellers from different countries.
C) They are especially useful when buyers and sellers do not come into the market very often.
D) They earn a commission from whichever party hired them when the transaction is completed.
E) The broker's product is information about what buyers need and what supplies are available.