Describe the role of escalator leveling sensors.

The role of escalator leveling sensors is crucial for ensuring safety and comfort as they help maintain the steps of the escalator in alignment with the landing at the entry and exit points. This alignment is essential for providing a smooth transition for passengers getting on and off the escalator. If the steps are not level with the landing, it could lead to tripping hazards or difficulty for passengers, especially those with mobility challenges. By actively monitoring and adjusting the position of the escalator steps, these sensors prevent any discrepancies in height, thereby enhancing passenger safety and overall operational efficiency.

The other choices focus on aspects that do not directly relate to the primary function of leveling sensors. Tracking the number of passengers, controlling speed, or preventing overloading involves different components and systems within the escalator's overall mechanism. Hence, these functions, while important for escalator performance, do not describe the specific role of leveling sensors.