Cholecystokinin stimulates
(a) pancreas
(b) gall bladder
(c) secrete bile
(d) none of these

Options

A. pancreas
B. gall bladder
C. secrete bile
D. none of these

Explanation

**Step-by-Step Solution:**

1. **Understanding Cholecystokinin**: Cholecystokinin (CCK) is a digestive hormone that plays a crucial role in digestion. It is secreted by the cells in the duodenum, which is the first part of the small intestine.

2. **Function of Cholecystokinin**: The primary function of CCK is to stimulate the gallbladder to contract. This contraction leads to the release of bile into the small intestine.

3. **Bile and Its Role**: Bile is essential for the emulsification of fats, which aids in their digestion and absorption. CCK also has some effects on the pancreas, but its main action is on the gallbladder.

4. **Analyzing the Options**:
- (a) Pancreas: While CCK does stimulate the pancreas to secrete digestive enzymes, its primary role is to stimulate the gallbladder.
- (b) Gall bladder: This is the correct answer, as CCK primarily stimulates the gallbladder to release bile.
- (c) Secrete bile: While CCK leads to the release of bile, it does not directly secrete bile itself; it stimulates the gallbladder to release bile that has already been produced.
- (d) None of these: This option is incorrect as CCK does stimulate the gallbladder.

5. **Conclusion**: Based on the functions of cholecystokinin, the correct answer is (b) gall bladder.

**Final Answer**: (b) gall bladder

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