What was a popular trend in the 1990s?
a. disco
b. boy bands
c. barbershop quartets
d. all of the above

All of the Above

Explanation:

In the 1900's there were a wide range of musical types in vogue.

The famous ones includes The boy bands, this is a band comprising of boys or men who sings melodious tunes especially love songs.

Disco was also a major music played in the 1990's as this form of music was extremely rampant then.

The barbershop quartets are a group of men or women who sing in the barbershop to entertain. It was a trend in the 1900's as well.

i would think b and c

sounds like legend of zelda man