Wolf is a 30 years old man who had a history of peptic ulcer. He Suddenly suffered for severe pain on the upper abdomen for 5 hours, accompanied by sweating, irritability, and taking the antacids could not alleviate, considered the possibility of perforation with ulcer disease. Which is the most helpful sign in judging perforation( )
A.
bowel sounds disappeared.
B.
abdominal muscle tension.
C.
abdominal percussion note was tympany.
D.
positive abdominal shifting dullness.
E.
decreased abdominal breathing.