Because the lens goes direct to the light rays and it helps them to focus on light sensitive, and the corena act on a outermost when light strike the corena helps bends or "Refracts" into the income light onto the lens. The only problem it's not "Retina and optic nerve" because the Retina and optic nerve goes to connects the eyes to the brain. And it not B. because the and "Rods and Cone" are responsible for vision at the "Low lights Levels". Maybe it could be C. But the only problem is the "iris and the pupil" are at the ring shape that surrounds at the opening area. So your best answer will be D Lens and Corena. Have a Great day!
