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: Anaesthesia
Percentage of tetracaine used in eye surgery? 
Select and explain. 
A. 0.50%, B. 1%, C. 2%, D. 4%
A: 0.50%
Answer: A: 0.50% 
Explanation: Ans. is 'a' i.e., 0.5% Cataract surgery can be performed using topical anaesthesia alone. Tetracaine 0.5% and Lidocaine 4% can be used. Advantages of this method is that it avoids the potential complications with retorbulbar and peribulbar injections. Dsadvantages include the potential for eye movement during surgery, increased patient anxiety, and discomfo from the microscope light