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
Which of the following inhaled gas is used to decrease pulmonary artery pressure in adults and infants ? 
Select and explain. 
A. Nitrous oxide, B. Nitrogen dioxide, C. Nitric oxide, D. Nitrogen
C: Nitric oxide
Answer: C: Nitric oxide 
Explanation: Nitric oxide dilates pulmonary vessels both in infants (used in persistent primary pulmonary hypertension) as well as in adults (used in primary pulmonary hypertension).