This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory System Pa 2, Subject name: Physiology
O2 delivery to tissues depends on all/except 
Select and explain. 
A. Cardiac output, B. Type of fluid administered, C. Hemoglobin concentration, D. Affinity of hemoglobin for 02
B: Type of fluid administered
Answer: B: Type of fluid administered 
Explanation: Increased cardiac output would increase the O2 transpo to the tissues. Increased Hb concentration would also increase the O2 transpo. Affinity of Hb for O2 decreases in tissues; more O2 is liberated by Hb.