Not a sign of Right atrial enlargement:: (A) Prominent right heart border with increased convexity (PA view), (B) Prominent anterosuperior part of cardiac shadow (lateral view), (C) Obliteration of retrosternal clear space (Lateral view), (D) Haffman-Rigler Sign (Lateral view)
Answer is D. Haffman-Rigler sign - Horizontal distance of greater than 1.8cm between posterior aspect of IVC and Posterior border of heart - Sign of Left Ventricular enlargement.