<prompt> Lower esophageal sphincter tone is due toVasoactive intestinal peptideNitrous oxideAcetylcholinePancreatic polypeptide  <response>: Ans. c AcetylcholineRef: Bailey Love 26th ed. 988There are two types of control of LES via the Myenteric plexus: Excitatory cholinergic ganglionic neurons Inhibitory nitric oxide ganglionic neuronsFunctionally, inhibitory neurons mediate Deglutitive lower esophageal sphincter LES relaxation and the sequential propagation of peristalsis. 