Which of the Following Statements Pertaining to Mistakes Is True

Which of the following statements pertaining to mistakes is true?

A) If one party has made a mistake about the subject matter, a contract is voidable.
B) A person who has made the mistake of not reading a written document would still get relief.
C) Relief will be afforded to one whose mistake is caused by negligence, and if the person would suffer reasonable hardship if the mistake were not corrected.
D) If the dealer has to bear the risk of mistake, the contract is valid.
E) A mistake is unilateral if it has a material effect on the agreed-to exchange.