This Large, Fan-Shaped Muscle of the Upper Chest is the Prime

Question

This large, fan-shaped muscle of the upper chest is the prime mover of arm flexion.
A) serratus anterior
B) pectoralis major
C) deltoid
D) external oblique

Accepted Answer

The pectoralis major is the large, fan-shaped muscle located in the upper chest, primarily responsible for arm flexion, among other movements.