Final answer:
Bob Dylan's fans were outraged when he played rock music at the Newport Folk Festival in 1965, marking a significant shift from his traditional acoustic folk songs to electric rock performances.
Step-by-step explanation:
At the Newport Folk Festival in 1965, Bob Dylan's fans were outraged when he appeared wearing a black leather jacket and played rock music. Dylan, a symbolic figure of social change and a proponent of the civil rights movement and anti-Vietnam War sentiment, had originally been associated with folk songs advocating for justice and inclusion. This switch to an electric performance signified a startling departure from his acoustic protest songs, leading to accusations of betrayal by his fans who expected him to maintain the folk genre that, to them, represented their cause. Dylan's fusion of electric instruments with sounds from various genres, including gospel, blues, country, jazz, and R&B, contributed to the evolution of rock music, which became increasingly popular among the youth of the era, much to the dismay of older generations.