This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General surgery, Subject name: Surgery
Water soluble contrast made up of 
Select and explain. 
A. Iodine, B. Barium, C. Calcium, D. Bromine
A: Iodine
Answer: A: Iodine 
Explanation: There are two types of Water soluble contrast:- Ref:- Surgery Sixer 3rd Edition; Pg num:- 327