Final answer:
The train operator should have stopped at the train signals, recognized the man waving the lantern as the signal maintainer, and proceeded with restricted speed and caution.
Step-by-step explanation:
The train operator should have stopped at the train signals, recognized that the man waving the lantern is the section signal maintainer, and proceed with restricted speed and extreme caution. The man waving the lantern is a signal maintainer, which means he is responsible for maintaining and inspecting the train signals. When the train operator sees the man waving the lantern, it indicates that there may be an issue with the signals or the tracks ahead, and it is important to proceed with caution to ensure the safety of the train and its passengers.