Explanation
(A) Women who begin menarche late (after 13 years old) have a lower risk of developing breast cancer than women who have begun earlier. Average age for menarche is 12.5 years. (B) Women who have never been pregnant have an increased risk for breast cancer, but a positive family history poses an even greater risk. (C) A positive family history puts a woman at an increased risk of developing breast cancer. It is recommended that mammography screening begin 5 years before the age at which an immediate female relative was diagnosed with breast cancer. (D) Early menopause decreases the risk of developing breast cancer.