NEED HELP!!!! 15 POINTS!!!!

Which BEST explains why it is important to warm up before strenuous exercise?
A.
It is very hard on the joints when exercise begins without warm up.
B.
It strains the muscles if blood and oxygen levels are not already activated.
C.
Warm-ups limit the oxygen supply, prepping the body for the rush during exercise.
D.
An exercise session should not include more than 30 minutes of aerobic activity.