From where do the internal mammary arteries arise?

• A. Aorta
• B. Femoral arteries
• C. Subclavian arteries
• D. Carotid arteries

Answer: (C)

The internal mammary arteries, also known as the internal thoracic arteries, originate from the subclavian arteries. Each subclavian artery gives rise to a left and a right internal mammary artery that descends vertically along the inner aspect of the rib cage. These arteries play a crucial role in supplying blood to the anterior thoracic wall, including the breasts, which is particularly important during surgical procedures like coronary artery bypass grafting, where segments of the internal mammary artery are often harvested for use as grafts.

The other choices do not serve as sources for the internal mammary arteries: the aorta is the major artery from which many vessels arise, but it does not give rise to the internal mammary arteries specifically; the femoral arteries are located in the lower extremities and are not involved in providing blood supply to the thoracic region; and the carotid arteries primarily supply the head and neck region, making them unrelated sources for the internal mammary arteries.