Which environmental factor can contribute to increased rodent populations?

The correct answer highlights the connection between food availability and rodent population growth. Rodents are opportunistic feeders, and the accumulation of food waste provides a consistent and readily accessible source of nourishment. When food waste is not properly managed, it creates an ideal environment for rodents to thrive, as they can easily find the sustenance they need to reproduce and survive.

Factors like low humidity, high levels of noise, and excessive lighting do not provide the same critical resource for rodents. While these conditions may affect their behavior or habitat preferences, they do not directly contribute to their population increase in the way that plentiful food sources do. Thus, the accumulation of food waste stands out as the primary environmental factor that can significantly boost rodent populations.