Question: Box Step is a basic dance step named after the pattern it creates on the floor, which is that of a square or box, it is used in a number of American Style ballroom dances, include Rhumba, also known as ballroom rumba, is a genre of ballroom music and dance that appeared in the East Coast of which country, during the 1930s?
Sentence (from "Rhumba"): Rhumba, also known as ballroom rumba, is a genre of ballroom music and dance that appeared in the East Coast of the United States during the 1930s.
Relevant evidence: Yes