The circulatory and respiratory systems work together to provide cells with oxygen and nutrients and remove waste products, such as carbon dioxide. When you need more oxygen, how does the circulatory stystem respond?

a
More blood is scent to the lungs and less blood is sent to the rest of the body.
b
The blood vessels to the arms and legs constrict to conserve oxygen.
c
The heart beats at a faster rate to match the rise in breathing rate.
d
Blood moves more slowly through the organs to carry away more wastes.