Which of the following indicates that the tire must be deflated before removal work?

For this question, the indication that the tire must be deflated before removal work is represented by a metal tag on the valve stem. A metal tag typically serves as a warning or instructional marker placed on or near the valve stem of a tire to alert personnel about specific safety protocols. In this case, it specifically signals that the tire must be deflated prior to maintenance or removal to prevent accidents, such as sudden tire blowouts or uncontrolled deflation. The metal tag acts as a clear visual reminder to ensure safety during tire servicing.

In a maintenance context, it's crucial for crew members to follow established protocols to mitigate risks associated with tire servicing. The presence of such a tag directs attention to the requirement of deflation, which is essential for safe tire handling and to prevent personnel injury.