I think C. You can't have just proteins or no fats in your diet. It needs to be balanced with a little of everything.
Answer and Explanation:
Split system training is a program of weight training that divides training sessions by body regions—usually upper- and lower-body training. For example, your weight training program includes a lower-body split on Tuesdays and an upper-body split on Thursdays.
Answer:
The 3rd Option
Explanation:
Simple for this question, C: an investigation because it uses only observations.