The fact that music that was popular in the 1990's isn't still listed at the top of the charts is an example of what factor that shifts demand?
a. income
b. consumer tastes
c. prices of related goods
d. consumer expectations

B. Consumer tastes

Explanation:

Music that was produced in the 1990s were done because of the particular demands and cultural reach of the people then. Music like High Life, Country, Soul, etc were extremely popular in the 1990s and the general public enjoyed listening to them

In the 21st century, the consumer taste had changed; gradually at first then rapidly. Genres of music like Hip Hop, Pop, Trap, Mumble Rap, became more popular. The surviving members of the 1990 era of Soul, Country music still listen to their old tapes and are happy.

Nowadays, any artiste that wants to enjoy sustained success in the music industry dare not venture into such faded musical genre because that's not what is on demand today.

Customer taste influenced greatly the type of music that was performed more than two decades ago.