Which of the Following Statements About Brazil's Participation in the Regional

Which of the following statements about Brazil's participation in the regional trade agreement MERCOSUR is true?

A) The formation of MERCOSUR required member countries to raise tariffs on imports from other members.
B) Brazil opposes the acceptance of new countries into MERCOSUR for fear of having its own exports undercut.
C) Brazil withdrew from MERCOSUR after allegations of currency fixing were leveled at the da Silva administration.
D) Disputes over currency valuation between Brazil and Argentina have been the chief dispute within MERCOSUR.