Here are 3 examples of research studies. Tell me which type of t test would be appropriate for each one (sample vs population; dependent; independent) and explain how you came up with the answer.

A: The researchers are comparing the Body Mass Index (BMI) of a group of male strength coaches to a group of female strength coaches.

B: The researchers are comparing BMI from a group of subjects pre and post a weight reduction program.

C: The researchers are comparing BMI of a group of subjects to an arbitrary standard of 25.