Answer:
<h3>Cardiorespiratory fitness (CRF) refers to the ability of the circulatory and respiratory systems to supply oxygen to skeletal muscles during sustained physical activity. ... Cardiorespiratory fitness helps improve lung and heart condition, and increases feelings of wellbeing.</h3>
The circulatory system is responsible for bringing food and oxygen to every cell in your body. The respiratory system is responsible for carrying oxygen and carbon dioxide in and out of your body.
Hope this helps
I'm pretty sure it's B. Tar
