Correct option is A
Correct Answer: (a) Only a
Explanation:
→ Anadromous salmonids typically have higher fecundity than non-anadromous individuals due to larger body size achieved in nutrient-rich marine environments.
→ Migration allows greater energy accumulation, improving reproductive output.
→ Statements (b) and (c) are true—migration enhances fitness and competitive ability.
Information Booster:
→ Anadromy is advantageous when marine feeding yields higher growth.
→ Energetic costs of migration are compensated by higher fecundity.