A warm up consist of a period of non-strenuous activity that slowly prepares the body for more vigorous exercise.
Most warm up will gradually increase in intensity. The muscle which was used can be different for each activity. <span>Not only athlete, </span>singer can do warm up too.
All of the above assuming yo also have a good diet
The answer is B. You don't want to put too much stress on those 2 areas or else they might get tired more easily