What rule indicates that signal indication will be the authority for a train to operate in either direction on the same track?

The rule specifying that signal indications serve as the authority for a train to operate in either direction on the same track is indeed the one referring to tracks that are signaled in both directions. This is essential for ensuring that trains can confidently move on such tracks, as the signal system provides the necessary information for safe operations.

When a track is signaled in both directions, signals provide clear guidance about the occupancy of the track and allow for movements from either direction based on the signal displayed. This contrasts with tracks that are only signaled in one direction, where operations are strictly limited to the direction indicated by the signal system.

Understanding this rule is crucial for safety, as it encompasses the protocols required for trains to communicate and operate on the same track without conflicts, ensuring efficient movement in both directions.