Answer: C.It builds up a higher level of oxygen in the blood.
Why does the heart automatically adjust the flow of blood to match activity levels?

Evolutionary psychology is a theoretical approach in the social and natural sciences that examines psychological structure from a modern evolutionary perspective. It seeks to identify which human psychological traits are evolved adaptations – that is the functional products of natural selection or sexual selection in human evolution. Adaptationist thinking about physiological mechanisms ...

The environmental impact of wind power is relatively minor when compared to that of fossil fuel power.Compared with other low-carbon power sources wind t...