Final answer:
Two examples of progressive rock bands are Led Zeppelin and Pink Floyd, as both have significantly contributed to the progressive rock genre with their complex compositions and thematic albums.
Step-by-step explanation:
When discussing examples of progressive rock bands, Option B) Led Zeppelin and Pink Floyd are correct. Progressive rock, often called prog rock, is known for its complex compositions, intricate instrumental segments, and lyrical themes that are often conceptual or based on fantasy and science fiction.
Both Led Zeppelin and Pink Floyd are quintessential bands within this genre and have significantly contributed to the evolution of rock music.
While Led Zeppelin's work sometimes borders on hard rock and heavy metal, they incorporated elements of progressive rock in their extended compositions and stylistic experimentation. Pink Floyd, on the other hand, fully embraced the progressive rock aesthetic with albums like 'The Dark Side of the Moon' and 'The Wall', becoming one of the leading bands of the genre.