This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Ophthalmology
One millimeter increase in the radius of curvature of cornea leads to hypermetropia of: 
Select and explain. 
A. 3 dioptres, B. 4 dioptres, C. 5 dioptres, D. 6 dioptres
D: 6 dioptres
Answer: D: 6 dioptres 
Explanation: Ans. 6 dioptres