Which of the Following Statements Is Correct with Respect to the Law

Which of the following statements is correct with respect to the law of consideration?

A) For a contract to be binding something valuable must have changed hands. This consideration may have been paid before the agreement (past consideration) or at the time of the agreement (present consideration) , but future consideration is no consideration.
B) Without consideration or a seal, there can be no contract.
C) The amount of consideration to be paid in a contract must be reasonable (that is, fair) from the point of view of each party.
D) Consideration must have some value but need not be specific.
E) Consideration need not be specific, just so both parties got something out of the deal.