What muscles do the nerves at the C5, C6, C7 root of the brachial plexus innervate

a) Triceps Brachii, Anconeus, and Brachialis
b) Biceps Brachii, Brachioradialis, and Pronator Teres
c) Deltoid, Pectoralis Major, and Latissimus Dorsi
d) Supraspinatus, Infraspinatus, and Teres Minor