Which of the following muscles are responsible for primary abduction of the arm at the shoulder joint?

[Joyce]

#january2020usmle2k

Which of the following muscles are responsible for primary abduction of the arm at the shoulder joint?

A- Coracobrachialis and deltoid
B- Deltoid and infraspinatus
C- Deltoid and supraspinatus
D- Supraspinatus and infraspinatus

 

[Tiffany Wong]

D- Supraspinatus and infraspinatus