Pick up the correct statement from the following: A. Rate of digestion of sludge is more at higher temperature B. Thermophilic organisms digest the sludge if the temperature ranges from 40° to 60°C C. Mesophilic organisms digest the sludge if the temperature is between 25° and 40°C D. All the above

The correct answer is D. All the above.

The rate of digestion of sludge is more at higher temperatures because the enzymes that break down the sludge are more active at higher temperatures. Thermophilic organisms digest the sludge if the temperature ranges from 40° to 60°C because these organisms are adapted to living in hot environments. Mesophilic organisms digest the sludge if the temperature is between 25° and 40°C because these organisms are adapted to living in moderate environments.

Here are some additional details about each option:

• Option A: The rate of digestion of sludge is more at higher temperatures. This is because the enzymes that break down the sludge are more active at higher temperatures. The rate of reaction doubles for every 10°C increase in temperature, up to a certain point. Beyond that point, the rate of reaction does not increase as much with increasing temperature.
• Option B: Thermophilic organisms digest the sludge if the temperature ranges from 40° to 60°C. Thermophilic organisms are adapted to living in hot environments. They are most active at temperatures between 40° and 60°C. At temperatures above 60°C, thermophilic organisms begin to die.
• Option C: Mesophilic organisms digest the sludge if the temperature is between 25° and 40°C. Mesophilic organisms are adapted to living in moderate environments. They are most active at temperatures between 25° and 40°C. At temperatures below 25°C, mesophilic organisms begin to die.

I hope this information is helpful!