Winnie, Who Is 49 Years Old, and Marian, Who Is

Winnie, who is 49 years old, and Marian, who is 51 years old, have both gone to their gynecologist.She tells each of them that they are showing signs of menopause, which refers to

A) an irregularity in menarche.
B) premature aging.
C) the end of regular monthly fertility cycles.
D) problems related to endometriosis.