I believe the answer is A. Achieving all of the above results.
Reason being because you need a certain amount of oxygen to support your muscles in every activity or your body will shut down.
The correct answer should be gymnastics. While the other mentioned sports could help him too, gymnastics is the most comprehensive one because it involves almost every muscle in the body to do various exercises, whereas biking would increase his leg muscle fitness most, but would not do much for the rest of his body.
The answer is A. millileters
<span>Good Morning!
Both contain truths. With the muscles accustomed to that amount of work, the effort is being reduced, since there is an increase of force. The work also assists in strengthening the heart, which is now more effective in pumping blood.
Hugs!</span>
