Which of the Following Statements Is Correct Concerning Aerobic Exercise

Which of the following statements is correct concerning aerobic exercise for young adults?

A) Exercise improves cardiovascular function by decreasing capillary diameter in the muscles and heart.
B) Raising heart rate to 150 beats per minute is not recommended for persons over the age of 25.
C) Young adults are encouraged to engage in activity that raises heart rate to 150 beats per minute.
D) Aerobic exercise should not be paired with muscle-strengthening activities so as to avoid over-taxing the heart.