Where an Agent Enters a Contract,not Under Seal,without Disclosing She

Where an agent enters a contract,not under seal,without disclosing she is an agent,the other contracting party

A) may bring an action for misrepresentation.
B) must first consent to ratification of the contract by the principal,for the principal to displace the agent.
C) may sue either the agent or the principal,but not both,if the principal is later revealed,and there is breach.
D) may sue either the agent or the principal,or both,if the principal is later revealed,and there is breach.
E) a and c.