The correct answer is: A. voidable at the option of the party making the proposal.
A contract is a legally binding agreement between two or more parties. In order for a contract to be valid, it must meet certain requirements, including that the parties must have entered into the contract voluntarily and with the intention of creating legal obligations. If one or both parties to a contract are mistaken about a material fact, the contract may be voidable at the option of the party who was mistaken.
A material fact is one that would have influenced the party’s decision to enter into the contract if they had known the truth. For example, if a buyer agrees to purchase a car that they believe is in good condition, but the car is actually in poor condition, the buyer may be able to void the contract.
The party who was mistaken must notify the other party of the mistake within a reasonable time after discovering it. If the other party does not agree to rescind the contract, the mistaken party may be able to sue to have the contract declared void.
Options B and C are incorrect because a contract is not considered valid if one or both parties are mistaken about a material fact. Option D is incorrect because a contract is not void if one or both parties are mistaken about a material fact.