A catadromous fish migrates from

Options

A. River to sea
B. Rivers to estuary
C. Sea to river
D. Deep sea to surface waters .

Answer

**Step-by-Step Solution:**

1. **Understanding Catadromous Fish**: Catadromous fishes are those that migrate from freshwater environments to marine (saltwater) environments.

2. **Identifying the Migration Path**: The key characteristic of catadromous fish is their movement from freshwater bodies, such as rivers, to the sea.

3. **Examples of Catadromous Fish**: A well-known example of a catadromous fish is the eel, specifically the genus Anguilla.

4. **Analyzing the Options**:
- **Option 1**: From river to sea - This is correct as it describes the migration of catadromous fish.
- **Option 2**: From river to estuary - This is incorrect because both river and estuary are freshwater environments, which would classify the fish as Potamodromus.
- **Option 3**: From sea to river - This describes anadromous fish, which migrate from marine to freshwater.
- **Option 4**: From deep sea to surface water - This describes Oceanodromous fish, which do not change the type of water they inhabit.

5. **Conclusion**: Based on the definitions and analysis of the options, the correct answer is that catadromous fish migrate from river to sea.

**Final Answer**: A catadromous fish migrates from river to sea.

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