A researcher is interested in determining if sleeping more hours the night before an exam will improve studentmath practice test scores. She randomly divides the class into two groups. One group is instructed to sleep 9hours. The other group is instructed to sleep 6 hours. Students were asked to complete a practice math test thefollowing day. The researcher then compares the average test score of each group. What is the best statistical testto analyze the data collected?O independent groups t testcorrelated groups t testone sample z testone sample t test

According to the question, the reasearcher randomly divides the class into two groups such that one is intructed to sleep hours and other is instructed to sleep hours. The groups were asked to complete test the following day. Then reasearcher compares the average test scores of each group.The correct statistical test for the given scenario is independent groups t test.Explanation :The independent groups t test is used to compare the means of two distinct samples or groups. Since the researcher divides the student in two groups then one group was instructed to sleep hours and other was instructed to sleep hours i.e., both the groups are independent. Hence, the correct statistical test to use is independent groups t-test.Correlated groups t test : The correlated groups t test cannot be used because this test is used when the same group is measured at two different intervals of time.One sample z test : This test cannot be used because it is used when only one sample is given.One sample t test : The one sample t test is also not appropriate because this statistical test is performed when only one sample is used.The correct answer is independent groups t test.