The correct answer is option b, that is, transduction.
The perceptual process refers to an arrangement of steps, which starts with the surrounding and results in the perception of a stimulus and an activity in reply to a stimulus. It can also be illustrated as the arrangement of psychological steps, which an individual utilizes to interpret and organize an information from the external world.
One of the steps in a perceptual process is transduction, which is a transformation of an image on the retina into electrical signals. This permits the visual messages to be conducted to the brain to be construed.