How do the digestive system and the circulatory system work together in the human body?

A. The digestive system sends electric messages, while the circulatory system responds to the messages.

B. The digestive system provides structure for the body, while the circulatory system directs the movement.

C. The digestive system removes liquid toxins from the body, while the circulatory system removes solid waste.

D. The digestive system extracts nutrients from food, while the circulatory system transports those nutrients.