Which of the Following Does Not Need to Be Proven

Which of the following does not need to be proven by a plaintiff who is claiming that an implied-in-fact contract exists?

A) The plaintiff provided property or services to the defendant.
B) The plaintiff and defendant communicated with each other about the property or services.
C) The plaintiff expected to be paid by the defendant for the property or services and did not intend to provide the property or services gratuitously.
D) The defendant was given an opportunity to reject the property or services provided by the plaintiff but failed to do so.