Final answer:
The part of Kiara's eye that is likely to be affected from a scratch by a foreign object is the cornea, which is the outer protective layer of the eye.
Step-by-step explanation:
If a foreign object has entered Kiara's eye and left a scratch, the part of her eye that is likely to be affected is the cornea. The cornea is the transparent, protective outer layer of the eye, which serves as a barrier between the inner eye and the outside world and is involved in focusing light waves that enter the eye. Unlike the lens, which aids in focusing images onto the retina, or the iris and pupil, which control the amount of light entering the eye, the cornea is the part that would be scratched by a foreign object due to its exposed position.