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: Pharmacology
Which of the following Iron is used for Parenteral Iron Therapy ? 
Select and explain. 
A. Iron dextran, B. Ferrous sulphate, C. Ferrous fumarate, D. Ferrous gluconate
A: Iron dextran
Answer: A: Iron dextran 
Explanation: Parenteral irons Oral irons Iron dextran Iron - sorbitol - citric acid Ferrous sucrose Ferric carboxy maltose Iron isomaltoside Ferrous sulphate Ferrous gluconate Ferrous fumarate Colloidal Ferric hydroxide Carbonyl Iron Iron requirement (mg) = 4.4 x body weight (kg) x Hb deficit (g/dl)