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: Radiology
Investigation of choice to differentiate pericardial effusion and dilatation of hea: 
Select and explain. 
A. Echocardiography, B. Angio cardiography, C. MR!, D. CT
A: Echocardiography
Answer: A: Echocardiography 
Explanation: Ans. Echocardiography