This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory System Pa 1, Subject name: Physiology
Maximum positive intrathoracic pressure is generated in: 
Select and explain. 
A. A forceful sneeze, B. A dry brassy cough, C. Blowing a trumpet, D. Valsalva maneuvre
D: Valsalva maneuvre
Answer: D: Valsalva maneuvre 
Explanation: A sneeze or a cough can generate a pressure of = + 30 and + 50 cm H2O. Blowing a trumpet can generate a pressure up to = + 80 cm H2O. Valsalva maneuvre (is a forced expiratory effo against closed glottis.) It can generate the pressure between = + 120 and + 150 cm H2O.