In which of the following fishes do dwarf males attach permanently to females as parasites and exhibit quasi-hermaphroditism?

Correct option is A

Correct Answer: (a) Deep-sea angler fish
Explanation:
→ Many deep-sea anglerfish species exhibit sexual parasitism where tiny males fuse permanently to the female’s body.
→ Once attached, male organs degenerate except gonads, functioning only for fertilization.
→ This relationship resembles quasi-hermaphroditism because female–male union forms a functional reproductive unit.
Information Booster:
→ Adaptation to extreme deep-sea conditions where mate encounters are rare.
→ Multiple males may attach to a single female.
→ Chemical and circulatory fusion enables resource sharing.
Additional Information (Other Options):
(b) Snook – protandrous species.
(c) Goby – some hermaphroditic forms but no parasitic males.
(d) Black porgy – capable of sex change but no parasitic mating.