Which of the Following Is NOT a Benefit or Quality

Which of the following is NOT a benefit or quality of breastfeeding?

A) Breast milk is naturally sanitary (less likely to lead to infant illness) .
B) Breastfeeding protects nursing women from certain forms of cancer.
C) Breastfeeding allows antibodies to travel from the mother to the infant.
D) Nursing women lose more calcium, which leads to higher bone density.
E) Breastfeeding is a natural form of birth control (although definitely not failsafe) .