Answer:
True. The smooth muscle of hollow organs and sphincters are generally under the control of the autonomic nervous system, which is divided into two branches: the sympathetic and parasympathetic nervous systems. The parasympathetic nervous system is responsible for promoting "rest and digest" functions in the body, which includes the relaxation of smooth muscle in the gastrointestinal tract and the contraction of sphincters. Therefore, it is true that the smooth muscle of hollow organs and sphincters are generally under the control of the parasympathetic nervous system.