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
Which of the following is true about hypoxic hypoxia? 
Select and explain. 
A. Due to inadequate carrying capacity, B. Due to inability to utilize oxygen, C. Due to inadequate gas exchange, D. Due to slow circulation
C: Due to inadequate gas exchange
Answer: C: Due to inadequate gas exchange 
Explanation: Ans. C Due to inadequate gas exchangeRef: Ganongy 25th ed. pg. 651* Hypoxic hypoxia is due to inadequate gas exchange, in which the oxygen content of arterial blood and PO2 are reduced. Example: COPD, High altitude.Types of Hypoxia and causesType of hypoxiaPathophysiologyExampleAnemic HypoxiaDue to reduced oxygen carrying capacityAnemia (Reduced RBC, Reduced Hb); CO poisoningHypoxic HypoxiaDue to Inadequate gas exchangeHigh altitude Respiratory disease (COPD)Histotoxic HypoxiaInability of cells to utilize available O2 Cyanide poisoningStagnant HypoxiaDue to slow circulationCirculatory Shock Congestive heart failure