The correct statement about how the nervous system interacts with other body systems is:
The nervous system controls the digestive system by sending signals to the stomach, telling it to contract and digest food.
This interaction highlights the role of the autonomic nervous system in regulating involuntary functions such as digestion. The statements about the circulatory and muscular systems contain inaccuracies, as the nervous system does not send signals to the heart to make more blood, nor does it send signals to ligaments to bond to tendons. The interaction with the skeletal system regarding movement is also an oversimplification, as the nervous system controls muscle contractions for movement, not directly sending signals to the legs themselves.