Question

What is physical fitness? the improvement of the body through intentional movement- the speed at which the body moves during exercise- the ability of the body to function efficiently during exercise- the performance of muscles for long periods of time

Answer 1

I would say it is the ability of the body to function efficiently during exercise <span />

Answer 2

I would say D) The performance of muscles for long periods of time. 

Because if you are physically fit, you can run, or exercise, or do other things without getting out of breath, and you can do them for a while.