Which of the following best explains why multiple exercises are needed to improve muscular strength and endurance throughout the body?
a. push-ups don't exercise leg muscle groups.
b. different exercises are needed to improve different muscle groups.
c. weight lifting is more important for muscle strength than endurance.
d. not all muscle groups can be exercised simultaneously.

B. Different excercises are needed to improve different muscle groups.

Explanation:

Answers A and C are too specific to their indivudal excercises and irrelevant to the question, and D disregards excercises that work out various parts of the body at once. B encompasses what you are trying to answer with the question, explains why different excercises are important, and is general enough to fully adress the broad question.

depends where it is? i got mine on my arm and from 1-10 it was a 3 different spots react differently