Where does the brachial artery begin?

The brachial artery begins at the lower border of the teres major muscle. This anatomical landmark is important as it signifies the transition of the axillary artery into the brachial artery after it passes through the axilla region.

The brachial artery continues down the arm, supplying blood to the muscles and tissues of the upper arm and eventually dividing into the radial and ulnar arteries at the elbow. Understanding this origin point is crucial for surgical procedures, vascular assessments, and diagnosing upper limb conditions.

The other options, while related to various anatomical structures and locations within the arm, do not accurately describe the specific starting point of the brachial artery. For instance, the cubital fossa is a region at the elbow; the upper border of the clavicle is related to the beginning of different branches and other arteries, and the midpoint of the humerus does not mark the beginning of the brachial artery's course.