Which of the following is not a fresh water fish?

Options

A. hilsa
B. catla
C. clarius
D. mystus

Answer

To determine which of the following is not a freshwater fish, we will analyze each option provided.

### Step-by-Step Solution:

1. **Identify the Options**: The options given are:
- A. Cutlass
- B. Katla
- C. Gladiolus
- D. Mischis

2. **Analyze Each Fish**:
- **Cutlass**: This fish is primarily a marine fish found in the Bay of Bengal. It is not a freshwater fish.
- **Katla**: Known scientifically as *Labeo catla*, this is a freshwater fish commonly found in rivers and lakes.
- **Gladiolus**: This is a type of catfish that is also a freshwater fish. It has the ability to walk on land and is found in freshwater bodies.
- **Mischis**: This is another type of catfish that thrives in freshwater environments, such as ponds and rivers.

3. **Conclusion**: Based on the analysis, the fish that is not a freshwater fish is the **Cutlass**.

### Final Answer:
The fish that is not a freshwater fish is **Cutlass**.

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