<prompt> The internal thoracic artery is a branch of -Arch of aortaSubclavian arterySuperior epigastric arteryThyrocervical trunk  <response>: Ans. is bi.e., Subclavian artery Internal thoracic arteryo It arises from 1st part of subclavian artery and descends through anterior ends of upper six intercostal spaces lying 1?25 cm lateral to sternal margin.o It divides into two terminal branches, musculophrenic and superior epigastric in 6th intercostal spaceo Branches of internal thoracic artery are:-i Mediastinal branchesii Pericardial branchesiii Sternal branchesiv Pericardiophrenic branchesv Anterior intercostal arteries in upper six spacesvi Perforating branchesvii Two terminal branches, musculophrenic and superior epigastric. 