This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'In iron deficiency anemia there is: \nSelect and explain. \nA. Decrease in hemoglobin, B. Increase in hemoglobin, C. Increase in platelets, D. Decrease in platelets', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]