Which of the followings is unsegmented and ovoviviparous worm ?

Options

A. Ascaris
B. Wuchereria
C. Taenia
D. Fasciola

Answer

To determine which of the following is an unsegmented and ovoviviparous worm, we need to analyze the characteristics of the options provided.

### Step-by-Step Solution:

1. **Understanding Unsegmented Worms**:
- Unsegmented worms are those whose bodies are not divided into distinct segments. This means they do not have the ring-like structures that are characteristic of segmented worms (like earthworms).

2. **Understanding Ovoviviparous**:
- Ovoviviparous organisms are those that produce eggs which develop inside the female's body. The eggs hatch within the female, and the young are born live. This is different from oviparous organisms, which lay eggs that develop outside the body.

3. **Evaluating the Options**:
- **Option A: Ascaris**:
- Ascaris is a type of roundworm. It is indeed ovoviviparous, but it is segmented. Therefore, this option is incorrect.
- **Option B: Wuchereria**:
- Wuchereria is a genus of parasitic worms that are unsegmented and ovoviviparous. They develop inside the female and are responsible for causing filariasis. This option is correct.
- **Option C: Taenia**:
- Taenia is a type of flatworm (tapeworm) and is segmented. Therefore, this option is incorrect.
- **Option D: Fasciola**:
- Fasciola is also a segmented flatworm (liver fluke). Hence, this option is incorrect.

4. **Conclusion**:
- Based on the analysis, the correct answer is **Option B: Wuchereria**, as it is unsegmented and ovoviviparous.

### Final Answer:
The unsegmented and ovoviviparous worm is **Wuchereria**.