The development team does monthly releases to the production system.

In Drupal 10 and Drupal 11, access to the site during maintenance mode is controlled through a specific permission rather than a configuration setting tied directly to roles on the maintenance mode page. The correct approach is to create a role and grant it the permission “Use the site in maintenance mode.” Users assigned this role will be able to bypass the maintenance mode restriction and access the site while it is offline for regular visitors.

Option C reflects this exact mechanism and aligns with Drupal core’s permission-based access control system. Drupal uses roles and permissions extensively to manage access, and maintenance mode is no exception.

Option A is incorrect because access is not limited strictly to administrators; it depends on permissions. Option B is incorrect because the Maintenance mode configuration page does not provide role selection for access—this is a common misconception. Option D is also incorrect because granting “Administer site” gives excessive privileges and is not required for maintenance mode access; it violates the principle of least privilege.

Therefore, assigning the “Use the site in maintenance mode” permission is the correct, secure, and Drupal-recommended solution.