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 is true because the nervous system plays a crucial role in regulating various functions of the digestive system, including controlling the contractions of the stomach and intestines through autonomic signals. The other statements contain inaccuracies regarding the interactions of the nervous system with other body systems.