The male fish are cut open, testes removed and squeezed to get milt in:

Correct option is A

Correct Answer: (a) Heteropneustes
Explanation:
→ In Heteropneustes fossilis, males do not easily release milt by stripping, so testes are removed by dissection.
→ Milt is squeezed out for artificial fertilization.
Information Booster:
→ This method is used due to the hard, compact gonads of catfishes.
Additional Information (Other Options):
(b), (c), (d): These can usually be stripped without dissection.