This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Blood, Subject name: Pathology
Earliest response to iron therapy is:(1995) 
Select and explain. 
A. Increase in Hb%, B. Reticulocytes, C. Increased PCV, D. Increased neutrophils
B: Reticulocytes
Answer: B: Reticulocytes 
Explanation: Ans: b