According to Hine, when did the concept of teenagers emerge in the UK?

The concept of teenagers as a distinct social group emerged in the UK during the 1950s, which aligns with the correct answer. This period marked significant cultural changes influenced by post-war prosperity, the rise of youth culture, and the emergence of rock and roll music. Teenagers began to be recognized not only for their age but also for their interests, styles, and social practices that differentiated them from both children and adults.

During this time, the notion of adolescence transitioned from merely being a period of transition into adulthood to one characterized by unique challenges, experiences, and identities. Various social phenomena, such as the growth of the media and consumer culture, further solidified the notion of the teenager.

While other time frames mentioned may have seen youth or young people, they did not encapsulate the modern understanding of 'teenagers' as a widely recognized demographic group with its own culture and social significance as seen in the 1950s. This decade is critical for understanding the evolution of youth identity in contemporary societies.