What might explain why adolescence has been elongated? the delayed onset of puberty recent brain imaging studies that have indicated that the prefrontal cortex is still developing until the age of 25 the failure of young adults to settle down in marriage-like relationships. the increased importance of formal education in making a successful transition into adult roles?

The correct answer is the last option: The increased importance of formal education in making a successful transition into adult roles.

Adolescence refers to a development phase in humans, that approximately occurs between childhood and adulthood. Adolescence begins after puberty onset, and involves the transition from childhood to adulthood. In present day society (especially in developed countries),the period of adolescence is elongated because before an individual transitions to adulthood, he or she is likely to undertake formal education that can end when the individual reaches 20-25 years of age.  

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