What does the term "pesticide" refer to?

The term "pesticide" specifically refers to a substance designed to kill, repel, or control pests. This broad category includes various types of chemicals that target organisms considered harmful, such as insects, weeds, fungi, and rodents. Pesticides are categorized into different types based on their intended use, such as insecticides for insects, herbicides for weeds, and fungicides for fungi.

In this context, the focus is on the functional role that pesticides play in pest management and agricultural practices. Understanding what pesticides are is crucial for effective pest control, as they are integral to managing pest populations and protecting crops, thus ensuring food security. The other options do not accurately capture the definition of pesticides; they refer to agricultural practices or substances that serve different purposes unrelated to the direct control of pests.