What is the action of marked muscle:

Ans. C. Protraction of scapula forward around the thoraxa. The muscle marked is Serratus anterior, it originates by nine or ten slips from either the first to ninth ribs or the first to eighth ribs. Because two slips usually arise from the second rib, the number of slips is greater than the number of ribs from which they originate.b. The muscle is inserted along the medial border of the scapula between the superior and inferior angles along with being inserted along the thoracic vertebrae,c. It is innervated by the long thoracic nerve (Nerve of Bell).The serratus anterior is occasionally called the "big swing muscle" or "boxer's muscle" because it is largely responsible for the protraction of the scapula -- that is, the pulling of the scapula forward and around the rib cage that occurs when someone throws a punch.