Breast level at midclavicular line -

Ans. is 'b' i.e., 2nd to 6th rib Mammary gland (Breast)o Breast (mammary gland) is a modified sweat gland present in the superficial fascia of pectoral regiono Vertically it extend from 2nd to 6th ribs at midclavicular line and horizonal extent is from sternal margin to midaxillary line at the level of 4th rib.Arterial supply of breast o Arterial supply of breast includes -1) Perforating branches of internal mammary artery in IInd, IIIrd, IVth intercostal spaces.2) Thoracoacromial, lateral thoracic and superior thoracic branches of axillary.3) Mammary branches, from 2nd, 3rd and 4th posterior intercostal arteries.Venous Drainageo There is an anastomotic circle of veins around the base of nipple-the circulus venosus of Haller. Veins from this and from the glandular tissue radiate to the circumference of the gland and drain into axillary, internal mammary and posterior intercostal veins.Nerve supplyo Sensory and sympathetic innervation is via anterior and lateral cutaneous branches of 4th, 5th and 6th intercostal nerves. Nipple is mainly innervated by the 4th intercostal nerve.