Under the Bretton Woods Exchange Rate System, Set Up in 1944

Under the Bretton Woods exchange rate system, set up in 1944, which of the following was true?

A) Americans could sell their dollars to the American government in exchange for gold.
B) Americans could sell their dollars to the American government in exchange for silver.
C) Americans could sell their dollars to foreign central banks in exchange for gold.
D) Foreign central banks could sell their dollars to the American government in exchange for gold.
E) Americans were required to pay for imports from other countries with gold.