Which of the following would create an express warranty?

a. A seller promising at the time of sale that he will repair any defects or problems
   for a year from the sale.

b. A seller showing the buyer a model and saying, “Yours will be just like this only
   blue instead of red.”

c. A seller taking a sample from a bin and indicating the purchase will conform to
  the sample.

d. All of the above create warranties.

e. None of the above create warranties.