John Has Been Hired by Bubbaweiser Beer Company to Purchase

John has been hired by Bubbaweiser Beer Company to purchase an airplane.He approaches Sam who has a Cessna for sale.John does not mention that he is making this purchase on behalf of someone else.He negotiates a deal.Two weeks later,Sam learns that John did not negotiate the deal for himself,but was acting as an agent.Bubbaweiser declares bankruptcy and cannot buy the plane.John:

A) can be held liable on the contract because this was an undisclosed agency
B) can be held liable on the contract because this was a partially disclosed agency
C) can be held liable on the contract simply because he is an agent
D) cannot be held liable on the contract
E) can be held liable on the contract unless he was on a frolic and detour