Anatomy Thorax 2923462c All of the following lie between the 1st rib and the apex of the lung, except A Thoracic duct B Superior intercostal aery C First posterior intercostal vein D Sympathetic trunk High-Yield Explanation Thoracic duct is in the posterior mediastinum . <img src=" /> Ref - BDC 6th editon vol 1 Pg275