Which of the following statements is consistent with the results of this experiment?

a) Providing a medium between the task and the ice cream had little effect on participants' willingness to perform a more effortful task.
b) The percentage of participants who preferred pistachio ice cream to vanilla ice cream was significantly higher in the experimental group, compared to the control group.
c) More than half of the participants in the experimental group chose the more effortful task, even though less than one - third actually preferred the type of ice cream awarded for that task.