Q. Which of the following could be digital input devices for computers?

Explanation by: Mr. Dubey

All the listed devices are digital input devices because they send data into the computer:
Scanner: Converts physical documents or images into digital form.
Microphone: Captures audio and sends it as digital signals.
Digital Camera: Captures photos or videos in digital format and transfers them to the computer.
So, all of them are correct input devices.