A 65-Year-Old Patient Is Admitted to the Progressive Care Unit

A 65-year-old patient is admitted to the progressive care unit with a diagnosis of community-acquired pneumonia.The patient has a history of chronic obstructive pulmonary disease and diabetes.A set of arterial blood gases obtained on admission without supplemental oxygen shows pH 7.35; PaCO₂ 55 mm Hg; bicarbonate 30 mEq/L; PaO₂ 65 mm Hg.These blood gases reflect:

A) hypoxemia and compensated metabolic alkalosis.
B) hypoxemia and compensated respiratory acidosis.
C) normal oxygenation and partly compensated metabolic alkalosis.
D) normal oxygenation and uncompensated respiratory acidosis.