Charlie tells Jamal that Marisol has agreed to allow him to sell her racing bicycle. Marisol is present at the time, hears the conversation, and says nothing. Jamal agrees with Charlie to buy Marisol's bike. Marisol then refuses to sell the bicycle. Marisol claims that she is not bound by the agreement formed by Charlie and Jamal because Charlie is not her agent. Marisol likely is:
a. not bound by the contract because she did not have an agency agreement with Charlie.
b. bound by the contract, under a theory of agency by operation of law.
c. not bound by the contract because of a rescission.
d. bound by the contract, under a theory of agency by estoppel.