Which one of the following is a marine fish ?

Options

A. Rohu
B. Hilsa
C. Catla
D. Common carp

Answer

To determine which of the following options is a marine fish, we will analyze each option based on their habitat:

1. **Understanding Marine and Freshwater Fish**:
- Marine fish are those that live in saltwater environments, such as oceans and salty lakes.
- Freshwater fish inhabit freshwater bodies like rivers and lakes.

2. **Analyzing the Options**:
- **Rohu**: This is a freshwater fish commonly found in rivers and lakes.
- **Hilsa**: This fish is known to inhabit marine environments, particularly in the sea.
- **Katla**: This is also a freshwater fish, typically found in rivers and lakes.
- **Common Carp**: This species is a freshwater fish that lives in ponds and rivers.

3. **Identifying the Marine Fish**:
- From the analysis, the only fish that is classified as a marine fish is **Hilsa**.

4. **Conclusion**:
- Therefore, the correct answer to the question "Which one of the following is a marine fish?" is **Hilsa**.

### Final Answer:
**Hilsa (Option B)** is a marine fish.