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
SRK formula is used to calculate 
Select and explain. 
A. Power of intraocular lens, B. Corneal curvature, C. Corneal endothelial cell count, D. Extent of retinal detachment
A: Power of intraocular lens
Answer: A: Power of intraocular lens 
Explanation: Answer- A. Power of intraocular lensIntraocular lens power calculation :- Which requires Keratometry (K), Axial length of eyeball or Biometry (L) and aconstant (A). It is calculated by SRK formula:Power of IOL= A- 2.5L -0.9K