This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory System, Subject name: Pediatrics
[{'content': 'Which one of the following values is not a feature of Acute Severe Asthma? \nSelect and explain. \nA. Heart rate more than 110/min, B. PEF of 60 to 70% of expected, C. Pulsus paradoxus, D. PaO2 of less than 8 kPa', 'role': 'user'}, {'content': "Answer: B \nExplanation: b. PEF of 60 to 70% of expected(Ref: Nelson's 20/e p 1095-1115, Ghai 8/e p 382-392)Note: 1kPa=7.5mmHg; So 8kPa=60mmHgGrading of severity of Asthma exacerbationCharacteristicsMildModerateSevereHeart rate<100100-120>120PEF (Peak expiratory flow)>=70% or response <40%40-69%<40%Pulsus paradoxusAbsentMay be presentOften presentPaO2 Normal>=60mmHg (8KPa)<60mmHg (8KPa)", 'role': 'assistant'}]