Name any annelid which is dioecious
(a) Pheretina
(b) Eisenia
(c) Nereis
(d) Lumbricus

Options

A. Pheretina Eisensia
B. Eisenia
C. Nereis
D. Lumbricus

Answer

To solve the question of identifying a dioecious annelid from the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Term Dioecious**:
- Dioecious organisms are those that have distinct male and female individuals. This means that a dioecious species will have individuals that are either male or female, but not both.

2. **Analyze the Given Options**:
- The options provided are:
(a) Pheretina
(b) Eisenia
(c) Nereis
(d) Lumbricus

3. **Evaluate Each Option**:
- **Pheretina**: This organism is known to be monoecious (hermaphroditic), meaning it has both male and female reproductive structures.
- **Eisenia**: Similar to Pheretina, Eisenia is also monoecious and possesses both male and female reproductive organs.
- **Nereis**: Nereis is known to be dioecious, meaning it has separate male and female individuals.
- **Lumbricus**: This organism is also monoecious and has both male and female reproductive structures.

4. **Identify the Correct Answer**:
- From the analysis, the only organism that is dioecious is **Nereis**. Therefore, the correct answer to the question is option (c) Nereis.

### Final Answer:
The annelid that is dioecious is **(c) Nereis**.

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