The most common source of pulmonary embolism is :

Ans. is 'c' large veins of leg (Ref Harrison, 17/e, p 1651 & 16/e, p 1561 (15/e, p. 1509)).Remember thatMC site for deep vein thrombosis - Calf vein*.But MC source for pulmonary emboli - Proximal vein of lower extremity (femoral vein*).