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
True about pain of pericarditis is -a) Pain increase on leaning forwardb) Pain decreasing on supine positionc) Pain increases during inspirationd) Pain increasing on eating 
Select and explain. 
A. ab, B. bc, C. bd, D. cd
D: cd
Answer: D: cd 
Explanation: None