2. (b) That's wrong. On these facts, A has the right to enforce the contract against C. B is acting as A's representative or agent, and whatever B does, it is as if A has done that thing himself. When B offers to buy the machine for $900, it is as if A were making that offer. When C communicates his acceptance to B, it is as if the acceptance were communicated to A.

A contract is thus created directly between A and C.