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
Following causes distension of abdomen-a) Hirschsprungsb) Hypokalemiac) Hyperkalemiad) Hypomagnesmia 
Select and explain. 
A. acd, B. bcd, C. abc, D. abd
D: abd
Answer: D: abd 
Explanation: None