Regular aerobic exercise gives an individual more endurance" is a sentence that shows cause and effect. which word indicates the cause?
a. individual
b. regular
c. endurance
d. exercise

The answer is letter D. 

Exercise is the operative word in the sentence which is the cause of gaining aerobic endurance. The other words are not an indication of the cause of aerobic endurance. Exercising plays an important role in overall fitness. It is always beneficial and has no known negative side effects. All persons should aim to exercise at least thirty minutes a day, three times a week. This improves overall health and is linked to preventing chronic diseases from happening to the body.

Why  do you think body composition focuses  on the  ratio  of  fatty tissue  to  other body tissue? why is  body composition not related  to  weight?

Its either c or d. i would go with d though, because im not sure if its legal in all of the us