Kristin Offers to Sell Land to Ian for $5,000

Kristin offers to sell land to Ian for $5,000.Ian says that $5,000 is too much but he will pay $4,000.Kristin says that she will not sell for $4,000.Two days later,Ian says that Kristin's original offer to sell for $5,000 is acceptable.Kristen says she no longer wishes to sell to Ian because he is a jerk.Which of the following is true about this situation?

A) There is a valid contract between Kristin and Ian for the sale of the land for $5,000.
B) Ian's counteroffer of $4,000 terminated Kristin's original offer, and she does not have to sell.
C) If Kristen does not sell to Ian for $5,000, then she cannot sell the land to anyone else for $5,000 or less.
D) The land can no longer be sold for $4,000 or less.
E) Kristen loses unless she can establish that Ian cannot come up with $5,000 within 10 days.