A viviparous fish is

Options

A. Labeo
B. Clarias
C. Gambusia
D. Exocoetus

Answer

To determine which of the given options is a viviparous fish, we need to analyze each option based on their reproductive methods. Viviparous organisms give birth to live young, while oviparous organisms lay eggs.

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Viviparous**: Organisms that give birth to live young.
- **Oviparous**: Organisms that lay eggs.

2. **Analyze the Options**:
- **Option A: Labio (Rohu Fish)**:
- The labio, commonly known as rohu, is a type of carp fish.
- It is **oviparous**, meaning it lays eggs.
- **Conclusion**: Incorrect option.

- **Option B: Clarias (Catfish)**:
- Clarias, also known as freshwater catfish, is another fish species.
- It is also **oviparous**, meaning it lays eggs.
- **Conclusion**: Incorrect option.

- **Option C: Gambusia (Mosquito Fish)**:
- Gambusia is commonly referred to as mosquito fish.
- It is **viviparous**, meaning it gives birth to live young.
- **Conclusion**: Correct option.

- **Option D: Exocetus (Flying Fish)**:
- Exocetus, known as flying fish, is another species.
- It is **oviparous**, meaning it lays eggs.
- **Conclusion**: Incorrect option.

3. **Final Conclusion**:
- The only fish among the options that is viviparous is **Gambusia** (Option C).

### Final Answer:
**A viviparous fish is Gambusia (Option C).**

---