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': 'Anterior focal point is at distance of ______in front of cornea in reduced eye - \nSelect and explain. \nA. 22-6 mm, B. 17-2 mm, C. 15-7 mm, D. 24-13 mm', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Point Distance in Listing&;s Reduced Eye Nodal Point 7.2 mm behing the anterior corneal surface Anterior Focal Point Posterior Focal point Anterior focal length Posterior Focal length Uniform Refractive Index 15.7mm anterior to anterior corneal surface 24.13mm behind anterior corneal surface 17.2mm 22.63 mm 1.336 Reference: Optics and Fefraction AK Khurana 7th edition page30,31', 'role': 'assistant'}]