Which one of the following structures in Pheretima is correctly matched with its function

Options

A. Typhlosle - storage of extra nutrients
B. Clitellum - secretes cocoon
C. Gizzard - absorbs digested food
D. Setae - defence against predators

Answer

To solve the question regarding which structure in Pheretima (earthworm) is correctly matched with its function, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understand the Structures and Their Functions**:
- We need to identify the structures mentioned in the options and their corresponding functions.

2. **Analyze Option A: Typhosol**:
- **Structure**: Typhosol
- **Function**: It is said to increase intestinal surface area for efficient absorption of digested nutrients.
- **Correctness**: This function is indeed true for Typhosol, but the question asks for the correct match. Typhosol is not primarily recognized for this function in the context of Pheretima. Thus, this option is **incorrect**.

3. **Analyze Option B: Clitellum**:
- **Structure**: Clitellum
- **Function**: It is a girdle that contains gland cells which secrete a substance that dries up to form a cocoon. This cocoon is where eggs and sperm are discharged, ensuring fertilization.
- **Correctness**: This option accurately describes the function of the Clitellum. Therefore, this option is **correct**.

4. **Analyze Option C: Gizzard**:
- **Structure**: Gizzard
- **Function**: It is located after the crop and is responsible for crushing food.
- **Correctness**: While this statement is true, it does not match the specific function as required by the question. Thus, this option is **incorrect**.

5. **Analyze Option D: Setae**:
- **Structure**: Setae
- **Function**: They help the earthworm attach to surfaces and prevent backsliding during peristaltic motion.
- **Correctness**: This function is true, but again, it does not match the specific requirement of the question. Thus, this option is **incorrect**.

6. **Conclusion**:
- After analyzing all options, we find that the only structure correctly matched with its function is **Option B: Clitellum**.

### Final Answer:
The correct answer is **Option B: Clitellum**, which secretes a cocoon for the discharge of eggs and sperms.