Best achievable results in Macrobrachium rosenbergii culture occurs at the temperature range of:

Correct option is C

Correct Answer: (c) 28–31 °C
Explanation:
→ M. rosenbergii is a tropical freshwater prawn that shows optimal growth, feed conversion and survival at warm temperatures around 28–31 °C.
→ Physiological rates (metabolism, digestion, molting) are best in this range, promoting faster growth and shorter culture cycles.
Information Booster:
→ Temperatures below this range slow metabolic processes and extend culture period; temperatures above the optimum increase stress, disease risk and mortality.
Additional Information (Other Options):
(a),(b): Lower than ideal — slower growth.
(d): Higher than optimum — may induce stress and disease.