The term "roaring twenties" gives the impression of prosperity, wealth, the jazz age, etc, but what were the underlying problems with the economy at the time? what types of people did not share in the prosperity of the twenties?

Poor people, especially farmers and African-Americans.

Explanation:

The Roaring Twenties refers to a period in the early 1920s in the United States. At the time, a few years after the end of World War I, cities in the US saw major development as a result of increased industrial output and economic growth. This combined with an urban population that was in the middle of a frenzy created by the new media, such as radio and cinema, created a false impression of a glamorous and prosperous life in the US. However, away from the cities and the urban upper classes, life was hard for a large part of the population, as around 40% of all Americans were poor. They did not share in the prosperity associated with the 1920s. Farmers were among the most affected. During and immediately after World War I, the US became the major food supplier of Europe, as the war had disrupted local production. However, as European farmers recovered, their counterparts in the US were left with increased production capacity and a surplus that they couldn't sell. Some of them were highly indebted as they had bought new equipment to cover the once high demand. Another very disadvantaged group were African-Americans, most of whom lived in the Deep South, as they were not only poor, but had to deal with the issues of racism and segregation. Eventually, the false image of the Roaring Twenties would crash down along with the stock market with the Great Depression of 1929.

the answer is a) high entry costs