Psychrotrophs grow best at which temperature range?

• A. Grow at low temperatures but prefer moderate; 15-30°C; max above 25°C
• B. Grow only at extremely cold temps below 0°C
• C. Grow best above 60°C
• D. Do not grow at any temperature below 20°C

Answer: (A)

Psychrotrophs can grow in cold environments yet prefer cool to moderate temperatures for optimal growth. They typically thrive around 15–30°C, and their growth is not limited to freezing conditions—they can also grow at temps above 25°C. This combination—capable of growth at low temperatures but with a growth optimum in the moderate range—defines them and explains why the statement describing growth at low temperatures with a preference for 15–30°C and a maximum above 25°C is the best fit. They are distinct from organisms that only tolerate extreme cold or only grow at much higher temperatures.