ll of the following offers are considered terminated, EXCEPT: a. Mary offers to buy Jeff's condo. Jeff does not like the price offered and counters with a new price. b. Mary offers to buy Jeff's unimproved property, but changes her mind and sends a written withdrawal Jeff before he accepts the offer. c. Mary offers to buy Jeff's 4-plex and the offer stipulates a 48-hour expiration to respond. Jeff does not consider the offer worthy of his attention and ignores it. d. Mary offers to buy Jeff's house. Jeff accepts the offer. Shortly after acceptance, Jeff is declared incompetent.