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
Best investigation for cardiac temponade is 
Select and explain. 
A. 2-D Echocardiography, B. M-Mode Echocardiography, C. Real time echocardiography, D. USG
A: 2-D Echocardiography
Answer: A: 2-D Echocardiography 
Explanation: A i.e. 2 D Echocardiography M- Mode Echo is also k/a One dimensional echo, it uses stationary beam so informations are updated very rapidly. It is often more conventient for assessing distance & motion of selected cardiac structure. 2-Dimensional echo has replaced it for most diagnostic purposes. It is expected that 3D imaging will replace most 2D imaging in future. 2-D-Echocardiography is investigation of choice for: Pericardial effusionQ Cardiac TemponadeQ Valvular hea ds Cardiomyopathy