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: Surgery
[{'content': 'Sonu, a 15 years old girl, a regular swimmer presents with sudden onset of pain in abdomen, abdominal distension and fever of 39deg C and obliteration fo the liver dullness. Most probable diagnosis is ? \nSelect and explain. \nA. Ruptured typhoid ulcer, B. Primary bacterial peritonitis, C. Ruptured ectopic pregnancy, D. UTI with PID.', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. is \'a\' ie. Ruptured typhoid ulcer The clue to this answer is presence of this clinical sign in the pt. --) Obliteration of liver dullness. Obliteration of liver dullness : Right mid-axillary line is percussed from above downwoards. The percussion note will be resonant in the upper pa of the mid-axillary line. At the upper border of the liver the resonant note in replaced by the dull note. If the liver dullness is replaced by a resonant note it indicates presence of free gas under the diaphragm as occurs in the perforation of the gastro-intestinal tract." - S.Das Manual, 4/e, p344 No other condition is able to cause obliteration of liver dullness.', 'role': 'assistant'}]