How can a small human retina detect objects larger than itself?
a.
the cells of the retina change the size of the images.
b.
lenses of the eye change the size of the images.
c.
the brain interprets the size of the images.
d.
the optic nerve interprets the size of the images.

Exactly the same way that you can photograph a mountain or a skyscraper
with the itty bitty camera in your smartphone.

Lenses are used to form a tiny image of a gigantic object.

The best answer is C."the brain interprets the size of the images"
Because, light reflects off the things in the world, then is focussed by our eye's lens. The light changes the light image we are seeing from the distal stimulus(or 3 diminutional world) to the proximal stimulus(or 2 dimensional world), but the image is not actually interpreted until it passes through the retina and optic nerve. The retina converts light into electrical impulses and the optic nerve carries those impulses to the brain. The Brain then changes the electrical impulses into a visual image.