A nurse is reinforcing teaching about colostrum with a new mother who is breastfeeding. The mother asks. "Why is colostrum so important for my baby?" Which of the following responses should the nurse make?

A. "Colostrum provides vitamin K, which is an essential nutrient for newborns.": Vitamin K is administered separately via injection at birth to prevent hemorrhagic disease. Colostrum contains minimal vitamin K and is not the primary source for newborns. B. "Colostrum provides many important antibodies that the newborn lacks.": Colostrum is rich in immunoglobulins, particularly IgA, which provides passive immunity and protects the newborn’s gastrointestinal tract from infections. These antibodies are crucial during the first days of life before the infant’s immune system is fully developed. C. "Colostrum contains a natural diuretic that stimulates the newborn to void.": While colostrum has a mild laxative effect, its primary purpose is nutrient provision and immune protection rather than acting as a diuretic. D. "Colostrum contains iron, which is important for a newborn's brain development.": Colostrum contains very low amounts of iron. Newborns rely on iron stores accumulated in utero, and breast milk alone does not provide sufficient iron for brain development in the first months.