All of the Following Statements About Express Warranties Are True

All of the following statements about express warranties are true except:

A) It is immaterial whether the express warranty is made at the time of the sale or after the sale.
B) Separate consideration is required to legitimize a warranty made at the time of the sale.
C) A warranty made after a sale may be considered a modification of the sales contract.
D) If a warranty made after a sale is a modification of the sales contract, no additional consideration is required.