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
Definitive sign of phase I of anaesthesia is – 
Select and explain. 
A. Fixation of eyeball, B. Pupillary dilatation, C. Blurring of vision, D. Intercostal paralysis
A: Fixation of eyeball
Answer: A: Fixation of eyeball 
Explanation: Plane 1 (Phase 1) of stage III ends when eye balls become fixed.