This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hematology, Subject name: Pediatrics
First change of improvement noted after iron therapy is initiated 
Select and explain. 
A. Decreased irritability, B. Reticulcytosis, C. Increase in serum iron levels, D. Replenishment of iron stores
A: Decreased irritability
Answer: A: Decreased irritability 
Explanation: First change of improvement noted after iron therapy is decreased irritability followed by increased reticulocyte count. Reference: GHAI Essential pediatrics, 8th edition