B
I had done a search on the internet
Answer:
The answer is B.
Explanation:
For just about everyone but especially for young and middle aged adults, because of their expected level of physical fitness, the single most important physical fitness component is "Cardiorespiratory Endurance" which is the term to measure how one's lungs, muscles and heart keep up together with intense exercise over a long period of time. Cardiorespiratory Endurance can be increased by correct nutrition and regular work-out sessions.
I hope this answer helps.
A biological cycle, or rhythm, that is approximately 24 hours long is called a circadian cycle
