This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Lens, Subject name: Ophthalmology
Posterior capsulotomy after cataract is done using 
Select and explain. 
A. Argon Laser, B. Nd YAg, C. Holmium, D. Diode laser
B: Nd YAg
Answer: B: Nd YAg 
Explanation: (Refer: AK Khurana Comprehensive Ophthalmology, 6th edition, pg no. 214 - 215)After cataract, if thin, can be cleared centrally by Nd: YAG laser capsulotomy. Dissection with cystitome or Zeigler&;s knife also be used. Thick membranous after cataract needs surgical membranectomy.