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
All of the following reduce T4 absorption except: 
Select and explain. 
A. Metformin, B. Iron salts, C. Raloxifene, D. Colesevelam
A: Metformin
Answer: A: Metformin 
Explanation: None