A client states, "I am legally blind." Which assessment technique should the nurse use to obtain subjective data to support the client's statement?

Observe the client's pupillary response to a penlight.

Observe the client's optic disc through an ophthalmoscope.

Observe the client's eye movements through the cardinal fields of vision.

Assess the client's ability to read a Snellen chart from a distance of 20 feet.