Which of the following is the most cranial structure in the root of left lung?

Ans. is 'b'i.e. Pulmonary artery Root of the lung is a short broad pedicle which connects the medial surface of the lung to the mediastinum.Contents of RootPrincipal bronchus on the left side, and eparterial and hyparterial bronchi on right side.One pulmonary artery.Two pulmonary veins, superior and inferior.Bronchial arteries, one on the right side and two on the left side.Bronchial veins.Anterior and posterior pulmonary plexuses of nerves.Lymphatics of the lung.Bronchopulmonary lymph nodes.Areolar tissue.Arrangement of Structures in the RootFrom before backwards. It is similar on the two sides.Superior pulmonary veinPulmonary arteryBronchusFrom above downwards. It is different on the two sides. Right side Left side Eparterial bronchus 1 .Pulmonary artery Pulmonary artery 2.Bronchus Hyparterial bronchus 3 .Inferior pulmonary vein Inferior pulmonary vein Relations of the Root Anterior Posterior Common on the two sides a. Common on the two sides 1 . Phrenic nerve 1 .Vagus nerve2. Pericardiophrenic vessels 2.Posterior pulmonary plexus 3 . Anterior pulmonary plexus b. On left side On the right side 1 .Descending thoracic aortaSuperior vena cavaA part of the right atrium. Superior Inferior On right side Pulmonary ligament Terminal part of azygos vein On left side Arch of the aorta