Osmoregulation or homeostasis is the function of 

Options

A. tufted nephridia
B. closed nephridia
C. both 1 & 2
D. enteronephric nephridia

Answer

To answer the question "Osmoregulation or homeostasis is the function of," we will analyze the options provided and determine which type of nephridia is responsible for these functions in organisms, particularly in earthworms.

### Step-by-Step Solution:

1. **Understanding Osmoregulation and Homeostasis:**
- Osmoregulation refers to the process by which organisms regulate the balance of water and salts in their bodies to maintain homeostasis. Homeostasis is the maintenance of a stable internal environment despite changes in external conditions.

2. **Identifying Types of Nephridia:**
- The question presents four options related to types of nephridia:
- **Tufted Nephridia**
- **Closed Nephridia**
- **Both Tufted and Closed Nephridia**
- **Enteronephric Nephridia**

3. **Analyzing Each Option:**
- **Tufted Nephridia:** These are branched nephridia found in earthworms. They play a role in excretion but are not primarily responsible for osmoregulation.
- **Closed Nephridia:** These are nephridia that do not open into the coelom and are involved in the excretion of waste. They also contribute to osmoregulation but are not the main type responsible for it.
- **Both Tufted and Closed Nephridia:** This option suggests that both types are responsible for osmoregulation, but this is not entirely accurate as neither is primarily responsible.
- **Enteronephric Nephridia:** These nephridia open into the intestine and are specifically adapted for osmoregulation and excretion in earthworms.

4. **Conclusion:**
- After analyzing the functions of each type of nephridia, it is clear that **Enteronephric Nephridia** is primarily responsible for osmoregulation and homeostasis in earthworms. Therefore, the correct answer is **Enteronephric Nephridia**.

### Final Answer:
Osmoregulation or homeostasis is the function of **Enteronephric Nephridia**.

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