The cryspts of lieberkuhn secrete `,`

Options

A. gastrin
B. rennin
C. cholecystokinin
D. succus entericus

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks what the crypts of Lieberkühn secrete. The crypts of Lieberkühn are glandular structures located in the lining of the small intestine.

2. **Identifying the Function of the Crypts**: The crypts of Lieberkühn are responsible for secreting various substances that aid in digestion. They play a crucial role in the digestive process.

3. **Types of Secretions**: The secretions from the crypts of Lieberkühn include digestive enzymes such as proteases, lipases, and amylases, which help in breaking down proteins, fats, and carbohydrates, respectively.

4. **Understanding the Term 'Succus Entericus'**: The combined secretions from the crypts of Lieberkühn and other glands in the small intestine are referred to as 'succus entericus'. This term encompasses all the digestive juices secreted in the small intestine.

5. **Final Answer**: Based on the information gathered, the crypts of Lieberkühn secrete 'succus entericus'.

### Answer:
The crypts of Lieberkühn secrete **succus entericus**.

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