Which of the following methods does NOT contribute to reducing pest populations?

The method that does not contribute to reducing pest populations is over-reliance on a single pesticide. This approach can lead to several issues, primarily pest resistance. When a single pesticide is used repeatedly, target pests can develop a tolerance to the chemical, making it less effective over time. This can result in higher pest populations since the pesticide no longer effectively controls them, creating a cycle that requires either higher doses or different products that may be harmful to non-target organisms and the environment.

In contrast, regular sanitation practices help reduce pest populations by eliminating food sources and breeding sites, thereby disrupting pest life cycles. Crop rotation is an effective method as it interrupts pest life cycles by planting different crops that pests may not be adapted to, reducing their populations over time. Biological control using natural predators is a sustainable approach that leverages the natural food web to keep pest populations in check without the negative consequences associated with chemical applications. Thus, relying solely on a single pesticide fails to embrace integrated pest management principles that promote long-term pest control solutions.