What does the optic nerve function primarily as?

The optic nerve primarily functions as a conduit for visual information. It transmits visual signals from the retina, where light is converted into electrical impulses, to the brain. This process is essential for vision, as the brain interprets these signals to create the images we see. The optic nerve consists of retinal ganglion cell axons, which collectively carry the visual information processed in the retina to the visual cortex in the brain for interpretation, allowing us to perceive our surroundings.

In contrast, the other options involve different functions related to vision but do not accurately describe the primary role of the optic nerve. The motor pathways for eye movement pertain to different cranial nerves responsible for controlling the muscles of the eye. Regulating pupil response involves both the iris and parasympathetic nervous system, which are separate from the optic nerve's role. Lastly, the control center for eye tracking is more related to the brain’s processing areas that coordinate eye movements rather than the optic nerve itself. Therefore, option B accurately captures the primary function of the optic nerve in the visual system.