When must all vessels containing liquor be cleared from all areas open to the public?

The correct choice is that all vessels containing liquor must be cleared from all areas open to the public prior to the legal closing time. This regulation ensures compliance with local laws regarding the sale and consumption of alcoholic beverages, protecting both patrons and staff by facilitating a smooth transition during closing hours.

Clearing vessels before the designated legal closing time helps to minimize potential disturbances and supports responsible alcohol service by ensuring that all patrons are informed and prepared to conclude their activities in a timely manner. This regulation is typically in place to avoid any complications that may arise if liquor remains available after the officially designated closing period, contributing to a safe environment for everyone involved. Therefore, adhering to this requirement is vital for maintaining safe and lawful operations in establishments serving alcohol.