Respuesta :
Target Heart Rate: is the maximum number of times your heart should beat per minute during exercise.
A) is for RHR (Resting Heart Rate) it is when you wake up.
D) You can't purchase your heart rate at a target store
C) is the correct answer because B) your target heart rate can be for ANY activity.
I would say B.) because when I research it in google, I found that its to improve your cardiovascular fitness