The passage suggests which of the following about the adolescent growth spurt that takes place in humans? A. Its primary effects are found in parts of the body other than the limbs. B. It is generally completed by the time 77 percent of full skeletal growth is attained. C. It is normally detectable without the assistance of sophisticated mathematical analysis. D. The rate of growth is much faster at the beginning of puberty than at any other time. E. The estimated growth rate varies depending on the methods of measurement that are used.