Answer:
d. a mutual mistake
Explanation:
Based on the information provided within the question in regards to the situation at hand it can be said that the contract between AJ and Harry can be rescinded because of a mutual mistake. This term refers to when both parties of a contract have made the same mistake in regards to an important detail or fact within the contract. Which in this scenario was that they both believed that the truck was strong enough to handle the trailer.
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