Consideration Can Have Legal Value

Consideration can have legal value:

A) if there is no proof of bargain between the promisor and promisee.
B) if the promisee does or agrees to do something,he or she had no prior legal duty to do,in exchange for the promisor's promise.
C) if the promisee agrees to do something he or she has a legal right to do in exchange for the promisor's promise.
D) if the promisee doesn't give up something in exchange for the promise made by the promisor.