When evaluating patient medications, the nurse knows which class of oral hyperglycemic agent lowers fasting blood glucose by triggering the release of insulin from beta cells?

Choice A reason: Amylin analogs slow gastric emptying and suppress glucagon secretion but do not directly stimulate insulin release. Choice B reason: Alpha-glucosidase inhibitors delay carbohydrate absorption in the intestine, affecting postprandial glucose but not fasting levels. Choice C reason: Biguanides (e.g., metformin) reduce hepatic glucose production and improve insulin sensitivity but do not stimulate insulin release. Choice D reason: Sulfonylureas stimulate pancreatic beta cells to release insulin, effectively lowering fasting blood glucose levels. This mechanism makes them suitable for patients with residual beta-cell function.