Final answer:
The crisis in young adulthood according to Erik Erikson is 'intimacy versus isolation,' where young adults must form intimate relationships without losing their newly formed sense of self.
Step-by-step explanation:
The crisis that arises in young adulthood according to Erik Erikson is concerned with intimacy versus isolation. Young adults, in their 20s through early 40s, are at a stage where having developed a sense of self in adolescence, they now face the challenge of forming intimate relationships with others versus facing loneliness and emotional isolation. Erikson emphasized that a strong sense of self is essential before developing these intimate relationships, and failure to do so may result in emotional isolation.