Answer:
CCK
Step-by-step explanation:
Cholecystokinin (CCK) acts by generating gallbladder contractions and relaxing the Oddi sphincter together with the action of secretin (another hormone secreted by the gut) that stimulates bile production and decreases acid secretion in the stomach.
When stomach acid is high, it stimulates the secretion of another hormone, secretin, which causes decreased gastrointestinal motility. This has the effect of stopping the transfer of stomach contents to the duodenum, preventing the stomach from emptying too quickly. Secretin in conjunction with CCK will also act on the stomach glands, inhibiting acid secretion.