DB Offered to Sell a Cap in Her Possession for $10

Multiple Choice

DB offered to sell a cap in her possession for $10. Dan said he would pay $5.

A) There is a contract for the sale of the hat for $10.
B) There is a contract for the sale of the hat for $5
C) There is no contract because Dan's counter-offer terminated his power of acceptance.
D) There is a contract if DB says nothing to Dan's proposal, because then her silence would be an acceptance.