Which BEST explains why aerobic training is the cornerstone of any fitness training? A. It is the simplest and easiest to get started with. B. Running is the one exercise that everyone should be doing. C. Once it is mastered, all other forms of exercise become much easier. D. It benefits the entire body in a way that other types of training do not.

when doing aerobics your body becomes more flexible, making it easier to do other exercises. Also, When doing any type of exercise more and more each day, your body starts to become use to all the work your doing and starts steading with the speed of your heart.

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