Which one of the following is a marine fish :

Options

A. Rohu
B. Hilsa
C. Catla
D. cyprinus

Answer

**Step-by-Step Solution:**

1. **Understanding the Types of Fish**:
- Fish can be categorized into two main types: freshwater fish and marine fish. Freshwater fish thrive in water bodies with low salt content, such as ponds, lakes, and rivers. In contrast, marine fish are adapted to live in saltwater environments, such as oceans and seas.

2. **Identifying the Options**:
- The options given are Rohu, Hilsa, Cutla, and Cyprinus. We need to determine which of these is a marine fish.

3. **Analyzing Each Option**:
- **Rohu**: This fish is scientifically known as Labio rohita and is classified as a freshwater fish.
- **Hilsa**: This fish is known for being a marine fish, commonly found in saltwater.
- **Cutla**: Also known as Katla (scientific name: Katla katla), this is another freshwater fish.
- **Cyprinus**: Commonly referred to as common carp, this fish is also a freshwater species.

4. **Conclusion**:
- Among the options provided, the only marine fish is **Hilsa**. Therefore, the correct answer is **Hilsa**.

**Final Answer**: Hilsa (Option 2) is the marine fish.

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