Which of the following is an example of a mechanical control method?

The correct choice is identified as an example of a mechanical control method because traps and barriers physically prevent pests from accessing certain areas or reduce their populations through capture. Mechanical control methods involve the use of physical devices or structures to manage pest issues without the application of chemical agents.

Traps can be used to capture insects or rodents, while barriers can prevent pests from entering specific areas, such as using screens to keep insects out of buildings or row covers to protect plants in a garden. This method is often valued for its environmental safety and effectiveness in reducing pest numbers while minimizing harm to non-target organisms.

In contrast, insecticide sprays, soil fumigation, and natural repellents primarily rely on chemical means or biological interaction to control pests, which do not fall under the category of mechanical controls.