Needing some help to clarify this problem and help finding the right answer.

Question

_b___ 2. Which of the following accurately describes the critical region?
a. outcomes with a very low probability if the null hypothesis is true
b. outcomes with a high probability if the null hypothesis is true
c. outcomes with a very low probability whether or not the null hypothesis is true
d. outcomes with a high probability whether or not the null hypothesis is true

Answer 1

The critical region CR, or rejection region RR, is a set of values of the test statistic for which the null hypothesis is rejected in a hypothesis test. That is, the sample space for the test statistic is partitioned into two regions; one region (the critical region) will lead us to reject the null hypothesis H0, the other will not. So, if the observed value of the test statistic is a member of the critical region, we conclude "Reject H0"; if it is not a member of the critical region then we conclude "Do not reject H0".