Carla has just written out a check for $18,999 to pay for her new car. Although the salesperson had initially accepted her check, she is now told that there was a mistake and that the final total should really be $19,250. Carla writes another check to cover the difference so that she can drive out with her new car. Carla has just fallen prey to a questionable sales practice called __________.

a. "lowballing."
b. "bait-and-switch."
c. the "dissonance game."
d. "keep ‘em guessing."