Which keyword would you most likely find on a Product Label indicating caution?

The presence of the keyword "Warning" on a product label signifies that caution must be exercised when using the product. This indicates that there are potential hazards associated with the product that users need to be aware of to ensure their safety. The term typically alerts consumers to possible risks or adverse effects that may arise if the product is not used as directed.

In contrast, terms such as "Safe," "Approved," and "Recommended" suggest a reassurance of efficacy or endorsement without necessarily indicating the need for caution. "Safe" implies that the product can be used without concern for adverse effects. "Approved" indicates that the product has met specific standards or regulations, but it does not address any hazards. "Recommended" suggests a suggestion for use, but again lacks the cautionary tone that "Warning" conveys. Therefore, "Warning" is the correct choice when discussing caution on product labels.