To prevent and control juvenile delinquency, it is far from enough to rely only on the protection of family, school and society, to persist in exercise, to improve physical fitness, and to improve cultural level and professional skills. Teenagers consciously regulate behavior, consciously exercise self-discipline according to law, and actively practice morality is more in line with the requirements of the topic, so ABC does not meet the meaning of the question, and option D is the correct answer.
So choose D.