Correct answer choice is:
D. Undergo a thorough physical examination.
Explanation:
Aerobic exercises include running, swimming, walking, hiking, dancing, skiing, and kickboxing. Aerobic exercises can become anaerobic exercises if performed at a level of intensity that is too high. Before starting such a routine, one should go for a proper physical examination because if you are not fit these exercise or for instance, any of you joint is injured or your lungs are not working properly and the heart rate is not normal, it may cause further troubles for you.
