This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Microbiology
Decreased O2 carrying capacity and Normal PO2 is a feature of 
Select and explain. 
A. Anemic hypoxia, B. Histotoxic hypoxia, C. Stagnant hypoxia, D. Hypoxic hypoxia
A: Anemic hypoxia
Answer: A: Anemic hypoxia 
Explanation: Subnormal level of haemoglobin causes decreased oxygen - carrying capacity of the blood. This, in turn, initiates compensatory physiologic adaptations such as :Increased release of oxygen from hemoglobin. o Increased blood flow to the tissues.Maintenance of the blood volume; andRedistribution of blood flow to maintain the cerebral blood supplyEventually, however, tissue hypoxia develops causing impaired functions of the affected tissues.