In type - II respiratory failure, there is :

Answer is B (Low PO2 and high PCO2): Type II respiratory failure (or pump failure) is characterized by decreased Pa02 and increased PaCO2 as a result of alveolar hypoventilation. There is a fall in minute ventilation which causes a rise in PaCO2 and fall in Pa02. The alveolar aerial gradient (PaO2 is normal). Type I Respiratory failure Hypoxemia with decreased PaCO2 Type II Respiratory failure Hypoxemia with increased PaCO2