A 23-year-old woman is noticed to have irregular pupils on routine examination. She has 1 large pupil, which has minimal response to light stimulation, but it does respond to accommodation. The eye movements are normal and she experiences no double vision.For the above patient with a pupillary abnormality, select the most likely diagnosis.
essential anisocoria Horner syndrome tonic pupils (Holmes-Adie syndrome) Argyll Robertson pupils