Sydney Announces to Her Class That Bonus Points Will Be

Sydney announces to her class that bonus points will be available for written thought papers on a topic. She expects performance on tests to increase. Which statement is true?

A) She is wrong; the reward is not tangible and will not affect performance.
B) She is wrong; the reward is expected or has been announced ahead of time and is unrelated to the quality of the thought paper-both factors known to make reward detrimental to performance.
C) She is correct, because the reward is not contingent on the quality of the performance.
D) She is correct; rewards all have different strengths, but they all increase performance.