<prompt> Serratus anterior is supplied by which nerve?Long thoracic nerveSpinal accessory nerveDorsal scapular nerveAxillary nerve  <response>: ANSWER: A Long thoracic nerveREF: Gray s anatomy 40th ed chapter 46Serratus anterior is innervated by the long thoracic nerve, C5, 6 and 7, which descends on the external surface of the muscle. 