A School Psychologist Is Using a Depression Inventory—on Which a Score

Multiple Choice

A school psychologist is using a depression inventory—on which a score of 0 indicates no depression and a score of 10 indicates severe depression—to see if the level of depression in fourth graders in a particular class of 20 students differs from that of fourth graders in general at a school. The results of previous testing indicate that fourth graders at the school usually have a score of 5 on the scale, but the variation is unknown. The current sample of 20 fifth graders has a mean depression score of 4.4.
-The psychologist tests the null hypothesis that the level of depression of fourth graders in this class does not differ from fourth graders in general at the school and obtains a t score of -0.20.The decision regarding the null hypothesis would be to

A) reject it.
B) fail to reject it.
C) adjust the power.
D) increase the sample size.