The role of the nervous system in digestion primarily involves providing electrical signals to initiate and regulate the process of peristalsis, which is the coordinated contraction of the muscles in the gastrointestinal tract that moves food along the digestive system. Therefore, the correct answer to your question would be 1: provide electrical signals to initiate peristalsis.
While the nervous system does play indirect roles in digestion by interacting with other systems (like influencing enzyme release and blood flow), its primary function in this context is related to motor control and coordinating movements in the digestive tract.