The efficiency and output capacity of a low pressure distilling plant will be reduced if the last effect shell __________.

Correct Answer: Option B — brine density is too low

Low brine density indicates that the evaporator is not being concentrated effectively, often due to excessive blowdown or improper feed rates. This reduces the efficiency of the heat transfer process and overall output capacity, as the plant fails to maintain the necessary concentration gradients for optimal flash evaporation.