Which component is NOT part of the train control apparatus?

The passenger seating arrangement is not a component of the train control apparatus because it pertains to the layout and configuration of the train's interior designed for passenger comfort and seating capacity. The train control apparatus, on the other hand, includes components that are essential for the operation and safety of the train.

The aspect display unit, automatic train control, and automatic train stop are all integral parts of the train control system. The aspect display unit provides visual signals to the train operator regarding track conditions and speed limits, while automatic train control systems help manage the movement of the train to ensure it operates safely and efficiently. The automatic train stop is a safety feature that automatically halts the train in certain situations, further demonstrating its role in train operation. Thus, these components directly contribute to the functionality and safety of train control, distinguishing them from the seating arrangement, which serves a different purpose entirely.