Answer:discharge by frustration of purpose
Step-by-step explanation:
Discharge by frustration of purpose is a defense concept used in law in order to bring about a breach or termination of a contract.This occurs when unplanned,spontaneous or unforeseen circumstances occurs and thus,it prohibits or prevents the core reason in which the contract was being entered into at the time of the contracts agreement,with both parties fully aware of the core reason which brought about the establishment of the contract.That is to say,the primary objective in which the contract was being created upon has automatically brought about a halt of the secondary reason(which is the contract itself),having in mind that both parties were originally aware of the primary reason for entering the contract.
Here,Paul and Patti Smith rented a room an amount triple it's original price because they were so excited to hear Lincoln speak. A day before Lincoln's speech, he was assassinated.So this disappointment brought about a "discharge by frustration of purpose" by the Smiths,not forgetting that that The bed and breakfast knew it was their original intent,that's why they paid such exorbitant prices for the room rental,although it sued them.