Anatomy All of the following muscles of the pectoral girdle are innervated by branches from the brachial plexus: except: A Subclavius B Serratus anterior C Rhomboid major D Trapezius 💡 Explanation All of the following muscles of the pectoral girdle are innervated by branches from the brachial plexus: except: ✓ Correct Answer: D. Trapezius