In Actual Practice, the Usual Reason for Determining Power Before

In actual practice, the usual reason for determining power before conducting a study is to:

A) eliminate the possibility that a mistake may occur
B) ensure that regardless of whether the research hypothesis is true, the experiment will yield a significant result
C) determine the number of participants needed to have a reasonable chance of getting a significant result if the research hypothesis is true
D) recognize the likelihood that the experiment will need to be repeated