To what does the term roaring 20s refer?

The term "Roaring '20s" refers to the decade of the 1920s in the United States, which was a time of much economic growth, as well as much social and cultural change.

In the 1920s, cities grew rapidly and industry was growing immensely in the United States.  Jazz and other forms of entertainiment (like radio) were expanding and reaching new audiences.  Women were becoming more involved in public life.  The stock market was a place of much speculation and investment -- too much, as it turned out.  The stock market crashed in 1929.   America had thought it was in great times during the Roaring '20s.  But then everything came crashing down and minds and hearts were depressed, as the country entered into the next decade and an economic tragedy known as the Great Depression. 

the answer is b. hope this !