Thelarche refers to the beginning of what in female puberty?

• A. Onset of menstruation
• B. Growth of body hair
• C. Deepening of voice
• D. Beginning of breast development

Answer: (D)

Thelarche is the onset of breast development, the first visible sign of puberty in girls. It happens due to rising estrogen, starting with breast budding and the growth of ductal tissue. This change usually appears around ages 8–13 and typically occurs before menarche (the first menstrual period).

Other changes listed—onset of menstruation, growth of body hair, and deepening of the voice—are different puberty milestones. Menarche follows thelarche, hair growth is driven by androgens, and deepening of the voice is characteristic of male puberty.