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: Pharmacology
[{'content': 'What is the formula for parenteral iron therapy in adults? \nSelect and explain. \nA. 4.4. x body weight (kg) x Hb deficit (g/dl), B. 3.3. x body weight (kg) x Hb deficit (g/dl), C. 2.2 x body weight (kg) x Hb deficit (g/dl), D. 1.1 x body weight (kg) x Hb deficit (g/dl)', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Parenteral iron therapy needs calculation of the iron requirement of the patient. Iron requirement (mg) = 4.4 x body weight (kg) x Hb deficit (g/dl). This formula includes iron needed for replenishment of stores. Iron stores can be replenished in a shoer time by parenteral therapy. Ref: Essentials of Medical Pharmacology by KD Tripathi, 5th edition, Page 549.', 'role': 'assistant'}]