This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Optics and refraction, Subject name: Ophthalmology
[{'content': 'Methods to measure errors of refraction are all except \nSelect and explain. \nA. Retinoscopy, B. Refractometry, C. Keratometry, D. Binocular balancing', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The final step in the subjective refraction is called "Binocular Balancing" - a process which is known as sometimes "Equalizing the accomodative effo" or "spherical equalization" This allows both eyes have the retinal image simultaneously in focus. Reference: AK khurana 7th edition', 'role': 'assistant'}]