The described changes - ovarian follicle development, mammary gland growth, and high-pitched voice - are all secondary sexual characteristics in females mediated primarily by estrogens. These steroid hormones, produced mainly by the ovaries, regulate female reproductive development and function.
Thus, the correct answer is (B) Estrogens.
Estrogens (option B) are the primary hormones responsible for the described changes in a sexually mature female. These steroid hormones, produced mainly by the ovaries, stimulate the development of ovarian follicles, promote mammary gland growth, and contribute to the characteristic higher-pitched voice by limiting the enlargement of the larynx compared to males. While progesterone supports pregnancy and androgens contribute to some secondary characteristics like pubic hair growth, estrogens are specifically responsible for the mentioned traits. Melatonin, involved in sleep regulation, has no direct role in sexual maturation.
Thus, the correct answer is (B) Estrogens.