Betty just celebrated her fiftieth birthday. she marked the occasion by taking hang-gliding lessons and purchasing a more mature wardrobe. according to levinson, betty is engaged in which developmental task?

 young-old      

Explanation:

              Daniel Levinson is a famous psychologist who is credited to have developed a complete theory in adult development. It referred to the stages and growth that takes place well in the adult years.

                This theory is known as Levinson's theory of Seasons of Life. According to Levinson's developmental task a person in his middle-age must look for new ways of being both young and old. This means that giving up some of the  youthful qualities and transforming others, in order to find positive meaning of being older. During this period of life people assess their success to meet new life goals.

             In the given context, Betty in her middle age celebrated her 50th birthday by taking a gliding lesson and also by buying a matured wardrobe which shows both her youthful and highly matured adulthood qualities. Hence Betty, according to the Levinson is engaging the "young-old"  stage of development task of adulthood.

Hence the answer is --

young-old

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