Which of the following is an indicator of an illicit laboratory?

Excessive security measures and concealed entrances are significant indicators of an illicit laboratory. Such facilities often require elevated levels of security to prevent detection and unauthorized access, reflecting the illegal activities being conducted within. Surveillance cameras, reinforced doorways, and hidden entry points suggest an intent to obscure operations from both public view and law enforcement scrutiny.

In contrast, brightly lit windows and open doors typically signify a legitimate operation, as they suggest transparency and regular activity. Regular and public access to the facility is also characteristic of lawful businesses, indicating an openness that would not typically be associated with illicit activities. Furthermore, standard laboratory equipment that is visible from outside implies a legitimate purpose, as legitimate businesses display their operations to attract clients or customers. Hence, the presence of excessive security and concealed access points serves as a clear red flag for the existence of an illicit laboratory.