The Muscles of the Arms and Shoulders Contain

 The muscles of the arms and shoulders contain

A) approximately equal amounts of fast- and slow-twitch fibers, making them well suited for both endurance and explosive movements.
B) higher proportions of slow-twitch fibers, making them better suited for endurance than for explosive movements.
C) higher proportions of fast-twitch fibers, making them better suited for explosive movements than for endurance movements.
D) higher proportions of fast-twitch fibers, making them better suited for endurance than for explosive movements.