Which among the following is the earliest indication of sexual maturation in a girl child?

Although the first measurable sign of pubey in girls is the beginning of the height spu, the first conspicuous sign is usually the development of breast buds (thelarche) between 8 and 11 years. Although breast development usually precedes the growth of pubic hair (pubarche), the sequence may be reversed. The growth spu stas at about age 9 years in girls and peaks at age 111/2 years, usually at SMR 3-4 breast development and stage 3 pubic hair development. The spu usually ends by age 14 years. The interval between the onset of breast development and menarche (onset of menstruation) is ~2 years. Also know: Sexual maturity rating (SMR) staging includes age ranges of normal development and specific descriptions for each stage of pubic hair growth, penis and testis development in boys, and breast maturation in girls. The first sign of pubey in the male, usually between ages 10 and 12 years, is scrotal and testicular growth. Ref: Sass A.E., Kaplan D.W. (2012). Chapter 4. Adolescence. In W.W. Hay, Jr., M.J. Levin, R.R. Deterding, J.J. Ross, J.M. Sondheimer (Eds), CURRENT Diagnosis & Treatment: Pediatrics, 21e.