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
Ewa's sign is seen in: 
Select and explain. 
A. Acute pulmonary embolism, B. Pericardial effusion, C. Pneumomediastinum, D. Chronic constrictive pericarditis
B: Pericardial effusion
Answer: B: Pericardial effusion 
Explanation: In pericardial effusion the base of the left lung may be compressed by pericardial fluid, producing a patch of dullness and increased fremitus (and egophony) beneath the angle of the left scapula. This is Ewa's sign. Ref: Harrisons principles of internal medicine, 18th edition, Page: 1971.