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
Thickness of cornea is best measured by: 
Select and explain. 
A. Keratometer, B. Pachymeter, C. Optometer, D. Pentoscope
B: Pachymeter
Answer: B: Pachymeter 
Explanation: Ans. Pachymeter