Catadromous fish migrate from:

Correct option is A

Correct Answer: (a) River to sea
Explanation:
→ Catadromous fishes like eels live in freshwater but migrate to the sea for spawning.
→ Adults undertake long migrations (e.g., to the Sargasso Sea).
→ Larvae return to freshwater to complete development.
Information Booster:
→ Opposite of anadromous migration.
→ Highly sensitive to migration barriers.
→ Used as ecological indicators of river health.
Additional Information (Other Options): Represent other migration types.