Certified Ophthalmic Assistant Practice Exam

During refractometry, cycloplegic drops are used to temporarily paralyze the ciliary muscles of the eye. This paralysis prevents accommodation, which is the eye's ability to adjust its focus for near vision by changing the shape of the lens. By inhibiting accommodation, cycloplegic drops allow for an accurate measurement of the eye's refractive error. Therefore, the correct answer is C. Pupil dilation is not impaired by the use of cycloplegic drops and may actually occur as part of the eye's response. Color vision and tear production are not directly affected by the use of cycloplegic drops during refractometry.