The intestinal hormone that stimulates the pancreas to release a watery, bicarbonate-rich fluid is .

The intestinal hormone that stimulates the pancreas to release a watery, bicarbonate-rich fluid is secretin.

Explanation:

Secretin is a hormone that stimulates the secretion of water and bicarbonate by pancreatic ductal cells. The secretion of this hormone by the duodenum and jejunum that stimulates the secretion of pancreatic juice, it's stimulated by the action of the chyme on the duodenal mucosa. This hormone passes into the blood and with it reaches the pancreas.

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