Martin Offered to Buy the Property for $200,000, "Offer to Remain

Multiple Choice

Martin offered to buy the property for $200,000, "offer to remain open until 5:00 p.m. on Thursday, January 21st." Which one of the following situations will not cause the offer to end?

A) Insanity of the offeror before the offer is accepted
B) Martin sells the property to another party before the expiration of the period stipulated and before hearing from the offeree.
C) A counter-offer from the offeree
D) Death of offeror
E) The offeree has not accepted and the stipulated time has expired.