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: Physiology
Hypoxemia independent of 
Select and explain. 
A. FiO2, B. Altitude, C. Hb, D. PaCO2
C: Hb
Answer: C: Hb 
Explanation: Hypoxemia is a condition of decreased aerial po2.Ref: Ganong review of medical physiology 24th edition Page no: 649