How does the pupillary response prevent injury? what would happen without it?

Part I

In extension to measuring the amount of light that enters the eye, the pupillary light reflex presents a helpful diagnostic tool. It provides for examining the uprightness of the sensory and motor functions of the eye. if your pupils didn't shut suddenly when abruptly disclosed to light, you'll get a tremendous shot of light (simultaneously with UV rays and other possibly dangerous rays) to your retina, which can severely mess up your vision.

Part II

Without it, we would go blind. If there is not sufficient light and the pupils do not dilate, a small number of light will pass to the retina and the image will be damaged.

you didn't give any options but heres what i can tell you: an inference is likely to change based on additional observations. the latter is something that you have seen or sensed using your sensory organs while the former is like a conclusion out from what you have observed.

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!