Which of the following scenarios would require refusal of service to a patron?

Refusing service to a patron who appears visibly intoxicated is essential for maintaining a safe and responsible environment in any establishment that serves alcohol. When a patron is visibly intoxicated, they may be unable to make sound decisions, which can lead to unsafe situations not only for themselves but also for others. Serving alcohol to someone who is already impaired increases the risks of accidents, altercations, and other negative consequences.

Additionally, many jurisdictions have laws in place that require servers to refuse alcohol to patrons who exhibit signs of intoxication. This is not only a best practice for responsible alcohol service but also a legal obligation in order to protect the establishment from liability. By refusing service in this scenario, the establishment is acting in the best interests of public safety and compliance with alcohol service regulations.

In contrast, the other scenarios—ordering food, asking for water, or celebrating a birthday—do not indicate any issues that would necessitate denying service or raise concerns about the patron's ability to responsibly consume alcohol. These scenarios typically involve behaviors that align with responsible drinking and do not present a risk to the patron or others.