What is typically similar across elevator systems but differs in input/output functions?

The correct choice highlights that while elevator systems often involve a common logic sequence for their operation, the specific input and output functions can vary significantly depending on the system design, manufacturer, and intended application. Elevator logic sequences serve as the framework that dictates how an elevator moves in response to commands, selects floors, and prioritizes certain operational protocols.

In many elevator systems, the fundamental logic—such as receiving a call, determining the optimal route, and executing the movement to the requested floor—is similar. However, input/output functions, such as how the system responds to calls or how it interfaces with other components, can differ based on technology, safety features, and user interface design.

Regarding the other options, power supply configuration can vary between systems but does not typically serve as a primary point of similarity across different elevators. Control panel design can also vary significantly, reflecting the manufacturer's choices and technologies used. Brake types can differ widely depending on the elevator’s design and load requirements, rather than sharing commonalities. Thus, the logic sequence stands out as the one consistent aspect across elevator systems while still allowing diverse adaptations for different functionalities.