Which one of the following is a marine fish ?

Options

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

Explanation

To determine which of the following options is a marine fish, we need to analyze the characteristics of each option provided.

### Step-by-Step Solution:

1. **Understand Marine Fish**: Marine fish are species that live in seawater, which is characterized by a higher salt concentration compared to freshwater.

2. **Examine the Options**: The options given are:
- Rohu
- Hilsa
- Katla
- Common Crab

3. **Identify Freshwater Fish**:
- **Rohu**: This is a freshwater fish commonly found in rivers and lakes.
- **Katla**: This is also a freshwater fish, typically found in rivers.
- **Common Crab**: While crabs can be found in both marine and freshwater environments, many species are marine.

4. **Identify Marine Fish**:
- **Hilsa**: This fish, also known as Hilsa sardine, is a marine fish that is found in seawater.

5. **Conclusion**: Among the options provided, the only marine fish is **Hilsa**.

### Final Answer:
The marine fish among the options is **Hilsa**.

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