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: Medicine
Which of the following iron therapy is associated with highest risk of anaphylasis? 
Select and explain. 
A. Ferric carboxy maltose, B. Iron dextran, C. Ferrous sulphate, D. Ferrous Fumarate
B: Iron dextran
Answer: B: Iron dextran 
Explanation: Anaphylasis is common with Iron dextran.