The end of adolescence and the beginning of adulthood varies by country and by function. Furthermore, even within a single nation state or culture there can be different ages at which an individual is considered (chronologically and legally) mature enough for society to entrust them with certain privileges and responsibilities. Such milestones include driving a vehicle, having legal sexual relations, serving in the armed forces or on a jury, purchasing and drinking alcohol, voting, entering into contracts, finishing certain levels of education, and marriage. Adolescence is usually accompanied by an increased independence allowed by the parents or legal guardians, including less supervision as compared to preadolescence.

Is adolescence usually accompanied by increased parental supervision or increased independence?