What is the average lifespan of an adult silverfish?

The average lifespan of an adult silverfish is indeed approximately 2 to 8 years, which makes this the correct answer. Silverfish are known for their resilience and ability to survive in various environments. Their lifespan can vary depending on factors such as food availability, temperature, and humidity.

Silverfish undergo a series of molts throughout their life, and unlike many other insects, they continue to grow and develop as they age, which can contribute to their longevity. The range of 2 to 8 years reflects the best conditions in which they thrive, allowing them to live longer than many other common household pests. This lifespan gives them a significant opportunity to reproduce and establish populations, making them an ongoing concern for pest control.

Other choices do not accurately reflect the longevity of silverfish; the more limited ranges understate their capabilities and survival strategies.