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
All except one are risk factors for obstructive sleep apnea 
Select and explain. 
A. BMI > 30.3, B. Feeling tired during daytime, C. Being treated for hypertension, D. Neck circumference >40cm
A: BMI > 30.3
Answer: A: BMI > 30.3 
Explanation: BMI > 35.6 is a risk factor for obstructive sleep apnea syndrome.