Which of the following best describes the required identification for trains and engines?

• A. Initial and number of the engine
• B. Trip origin and destination
• C. Engine type
• D. Crew initials and run number

Answer: (A)

Locomotives carry a unique identification stamped on them: the railroad’s initials (reporting marks) together with the engine’s number. This pair—initials and number—provides a precise, standardized ID that lets dispatchers, yard crews, and maintenance teams know exactly which locomotive is in service, where it’s from, and track its movements. It’s a stable identifier that stays with the engine, unlike route details or crew information. Trip origin and destination describes where the train is going, not which engine is in service; engine type identifies the kind of locomotive but not its specific identity; crew initials and run number identify the crew, not the engine itself.