What information must be included when responding to a radio call?

When responding to a radio call, it is essential to include both the employing railroad and the mobile unit identification. This information ensures clear communication and identification of the responding unit, which is critical in the busy and complex environment of rail operations. The employing railroad indicates the company responsible for the unit, while the mobile unit identification provides specific information about the location or operational status of that unit. This clarity helps in coordinating responses, enhancing safety, and allowing for efficient management of rail operations.

Other options, while they may contain relevant information in some contexts, do not encompass the mandatory identification that directly supports effective communication in response situations. Simply providing the name of the responding employee, weather conditions, or instructions from the dispatcher alone would not meet the standard requirements for clarity and accountability in radio communications on the railway.