For the consideration requirement in contracts to be met:

A) the consideration given by each party must be of roughly equal value.
B) each party must give consideration.
C) the consideration must have monetary value.
D) the consideration must consist of some form of property.

The requirement of consideration means that a promisee must pay the price that the promisor asked to gain the right to enforce the promisor's promise.So,if the promisor did not ask for anything in exchange for making him promise or if what the promisor asked for did not have legal value,his promise is not enforceable against him because it is not supported by consideration.