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: Unknown
Ramesh , 30 yrs old male,diagnosed case of CO poisoning presented with syncope or coma with intermittent convulsions, rapid respirations, tachycardia with a weak pulse and pink or red discolouration of the skin; estimated percentage of COHb : - 
Select and explain. 
A. 30 to 40 %, B. 40 to 50 %, C. 50 to 60 %, D. 60 to 70 %
C: 50 to 60 %
Answer: C: 50 to 60 % 
Explanation: None