What instrument provides information on a patient's refractive status by reflecting light off the retina?

The instrument that provides information on a patient's refractive status by reflecting light off the retina is the retinoscope. This device works by projecting a beam of light into the eye and observing the movement of a reflex as it hits the retina. The practitioner can analyze how the light reflects back from the retina, which helps in determining the refractive error of the eye. This process is known as retinoscopy.

In contrast, an ophthalmoscope is primarily used for examining the fundus of the eye, allowing practitioners to visualize the retina and other internal structures, but it does not assess refractive status in the same manner. A sphygmomanometer is entirely unrelated as it measures blood pressure, and a visometer is used to measure the size or diameter of an object, typically in other fields of measurement rather than directly related to eye examination. Therefore, the retinoscope is specifically designed for evaluating the refractive state of the eye, making it the correct answer.