Which of the Following Is an Example of the Structure

Which of the following is an example of the structure of your data when you are seeking a statistic for testing your study hypothesis?

A) You are examining the matched pretest and posttest scores for a group of clients.
B) You are examining the proportions of people in your study who have at least one child living in the home.
C) You are computing the mean salary of the people in your study sample.
D) You are computing the correlation coefficient between three variables.