What is the primary electrical difference between input devices and output devices?

A$.$ Input devices are considered loads, while output elements are considered devices.

B$.$ Input devices don't provide a path for current, while output devices do$.$

C$.$ Input devices only pass current and don't use it$,$ whereas output devices use current to operate.

D$.$ Input devices are always on the left side of the rung and output devices are always on the right side of the rung.