Popular music is said to reflect the tastes and preferences of which social class? upper class, middle class, lower class, underclass

The answer is Middle Class.

Many people in the Upper Class would prefer the classical music.  Classical music signifies status and class of a certain group of people while Popular Music often influences the Middle class or sometime the lower classes because this music is often heard by people in radios.

the answer to your question is,

old stone age.

-mabel < 3

yes he did writing dots to make the answer