Which of the following is an example of the interaction between the circulatory and respiratory organ systems in a human?

A.
The pancreas produces a rush of insulin when a child eats a lollipop.
B.
The toe of a standing woman hurts when a rock falls on it.
C.
The heart of a running man beats faster than the heart of a resting man.
D.
The nutrients in food are mechanically broken down in the stomach.