Which of the following describes signal words found on pesticide labels?

Signal words on pesticide labels are specifically designed to communicate the relative toxicity of the product to the user. They serve as an important safety feature, giving users an immediate indication of how hazardous the pesticide is. These words categorize the level of toxicity, helping users to understand the dangers associated with the pesticide without needing to delve into the detailed safety data sheets.

For instance, terms like "Caution," "Warning," and "Danger" signify different levels of toxicity, allowing users to make informed decisions about the necessary safety precautions to take while handling or applying the pesticide. This understanding is crucial for ensuring the safety of the applicator, bystanders, and the environment. The other options, while important aspects of pesticide labeling, do not pertain to the fundamental purpose of signal words.