50.下列何者是臂神經叢後索(posterior cord)支配闊背肌(latissimus dorsi)的分支？
(A)肩胛背神經(dorsal scapular nerve)
(B)下肩胛下神經(lower subscapular nerve)
(C)長胸神經(long thoracic nerve)
(D)胸背神經 (thoracodorsal nerve.)

1. 題目解析題目問的是哪一條神經是來...