Let's jot down the points:
R&R bands of 60s and 70s-not hit in 80s and early 90s
R&R major hit in late 90s
Why? We need to find that.
A. Not much good rock-n-roll was produced in the late 1990s.
INCORRECT. This is not of any help. Irrelevant or incomplete information.
B. These bands were able to blend elements of classic rock with the new sound of the late 1990s to appeal to a wide audience.
CORRECT. This can resolve the paradox tge perfect blend of old and new sound attracted their old fans as well as newbies of that decade.
C. The late 1990s saw an increasing nostalgia for the peace-loving era of the 1960s and early 1970s.
INCORRECT. If that's true then their old sound would be a hit and doesn't resolve paradox as to why the R&R bands are in demand and hit now.
D. The bands simply got better with age.
INCORRECT. What does this mean? The band practiced well for a decade or more? Lol no. The passage does mention about relative obscurity in 80s and 90s.
E. A new generation of listeners discovered classic rock.
INCORRECT. If yes, then they would go for old songs and not new. Doesn't resolve the paradox.
Thus, IMO answer is option B
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