"Jack told Jill that he was acting for a principal who did not want their name to be disclosed, and that he had authority to enter into contracts on behalf of this principal up to $500,000. After negotiating, Jack, supposedly as an agent, and Jill entered into a contract for $250,000. In fact, Jack was not an agent and there was no principal. Jack has now refused to complete the deal. Which is true?

A. Jill can sue Jack for breach of contract.

B. Jill cannot sue Jack for breach of contract, but can sue Jack in tort.

C. Jack is not bound by the contract because of a lack of privity.

D. The contract is void because of a lack of capacity.