Which of the following is a behavioral indicator of substance abuse in the workplace?

The correct choice, having a smell of alcohol, serves as a direct and sensory observable indicator of substance abuse in the workplace. When an individual is under the influence of alcohol, the scent can be noticeable to colleagues and can impact their perception of that person's behavior, performance, and overall fitness for duty. This physical manifestation is often one of the more recognizable signs that can raise concerns about an individual’s substance use.

In contrast, excessive participation in team activities, consistent punctuality, and a high level of productivity generally reflect positive attributes or behaviors that are not indicative of substance abuse. For example, engaging in team activities can suggest a positive and thriving work environment, while being punctual and productive are behaviors associated with professionalism and motivation. None of these traits serve as reliable indicators of substance abuse, which is why they are not appropriate choices in this context.