During which phase do bacteria rapidly reproduce?

Bacteria undergo rapid reproduction during the log phase. This phase is characterized by exponential growth, where the number of viable bacteria in a population increases dramatically due to optimal conditions such as sufficient nutrients, favorable temperature, and appropriate pH levels. During this phase, bacteria are highly active metabolically and are able to divide at their maximum rate.

The log phase follows the lag phase, where bacteria are acclimating to their environment and not yet reproducing at high rates. After the log phase, bacteria enter the stationary phase, where the growth rate slows and the number of viable cells stabilizes due to depletion of nutrients and accumulation of waste products. Eventually, in the decline phase, the population begins to decrease as resources are exhausted and conditions become unfavorable for growth. Thus, the log phase is distinct for its rapid bacterial reproduction, making it the correct answer.