Question

Appearance of antibiotic-resistant bacteria is an example of

• A. Adaptive radiation
• B. Transduction
• C. Pre-existing variation in the population
• D. Divergent evolution

Answer 1

Answer: (C)

Pre-existing variation in the population

When a bacterial encounters a particular antibiotic, those sensitive to it die. But some bacteria having mutations become resistant to the antibiotic. Such resistant bacteria survive and multiply quickly as the competing bacteria have died. Soon the resistance providing becomes resistant.

So, the correct answer is 'Pre-existing variation in the population'.