Axillary artery is divided into three parts by-
**Core Concept**
The axillary artery is a continuation of the subclavian artery, extending from the outer border of the first rib to the lower border of the teres major muscle. It is a vital part of the upper limb's arterial supply, and its division into parts is clinically relevant for surgical and medical purposes.
**Why the Correct Answer is Right**
The axillary artery is divided into three parts by the pectoralis minor muscle. This division is based on the anatomical relationship between the artery and the muscle. The first part of the axillary artery is proximal to the pectoralis minor muscle, the second part is behind the muscle, and the third part is distal to the muscle. This division is clinically important for the insertion of central venous catheters and for the diagnosis and treatment of axillary artery injuries.
**Why Each Wrong Option is Incorrect**
**Option A:** The axillary vein, not the axillary artery, is divided into three parts by the pectoralis minor muscle.
**Option B:** The axillary artery is not divided by the coracoid process or the clavicle.
**Option C:** The axillary artery is not divided by the teres major muscle.
**Clinical Pearl / High-Yield Fact**
The axillary artery's division into three parts is a classic example of how anatomical knowledge is essential for medical and surgical decision-making.
**Correct Answer: C. The pectoralis minor muscle.**