Which phrase indicates that a pesticide is highly toxic?

The phrase "DANGER/POISON" accompanied by a skull and crossbones is specifically designed to communicate a high level of toxicity associated with a pesticide. This labeling indicates that the product poses a significant risk to health if mishandled or misused. The skull and crossbones symbol is internationally recognized as a sign of poison, reinforcing the message that immediate danger is present.

In the context of pesticide labeling, terminology is carefully chosen to convey the potential risks. While the terms “WARNING” and “CAUTION” are also used on pesticide labels, they indicate lower levels of toxicity compared to "DANGER/POISON." A label that simply states "DANGER," though alarming, does not include the poison symbol and typically refers to hazards that can cause severe injury or death but may not be associated with the same level of immediate toxicity as "DANGER/POISON." Therefore, the presence of both the term "POISON" and the skull and crossbones firmly establishes option B as indicative of high toxicity.