A study of class payments for a local art studio found that individual painting classes students paid for directly had a cancellation rate of less than five percent, while those who signed up in advance for a twelve-class package had a cancellation rate of more than 25 percent. This might have been caused at least partially by the fact that the more aware students are of the cost of a course, the higher the chance that they will attend.
Which of the following would, if true, best serve as an alternative explanation of the results of the study?
【选项】
Those who attended all twelve classes were offered a partial refund.
选项是否正确？