The right option is b. growth of the breasts at puberty
Estrogen is a sex hormone and it is one of the most important hormones for women, together with progesterone. During puberty, estrogen hormones are released in line with each monthly menstrual cycle by the ovaries and it helps in the development and maintenance of female characteristics in the human body such as breasts, pubic and armpit hair. Estrogen also regulate the menstrual cycle and reproductive system of women.