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?
Context: Sequence dancing is a form of dance in which a preset pattern of movements is followed, usually to music which is also predetermined.  Sequence dancing may include dances of many different styles.  The term may include ballroom dances which move round the floor as well as line, square and circle dances. Do-si-do ( , ), dosado, or dos-à-dos (see spelling below) is a basic dance step in such dance styles as square dance, contra dance, polka, various historical dances, and some reels. Suzie Q (or Suzy Q) is the name of a dance step in the Big Apple, Lindy Hop, and other dances.  In line dances this step is also known as Heel Twist (actually refers to step 2) or Grind Walk.  The step is also used in jazz dance, and in Salsa shines. The dances that make up the list of DanceSport dances are performed competitively at amateur and professional levels throughout the world.  Ten international style ballroom dances—five Standard and five Latin—are defined by the World Dance Council (WDC), which has world-wide membership of all countries taking part in ballroom competitions. The varsovienne, also known as the varsouvienne or varsoviana, is a slow, graceful dance in time with an accented downbeat in alternate measures.  It combines elements of the waltz, mazurka, and polka.  The dance originated around 1850 in Warsaw, Poland.  The words "varsovienne" and "varsoviana" are French and Spanish feminine adjectives, respectively, meaning 'from Warsaw'.  The dance was popular in 19th-century America, where it was danced to the tune "Put Your Little Foot".  It quickly became a favorite folk dance in the Scandinavian countries as well.  The unique armhold by the same name – also known as the promenade hold – is used in other dance styles such as the American square dance, contra dance, and some ballroom dances. 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.  It combined American big band music with Afro-Cuban rhythms, primarily the son cubano, but also conga and rumba.  Taking its name from the latter, ballroom rumba differs completely from Cuban rumba both in its music and dance.  Hence, authors prefer the Americanized spelling of the word ("rhumba") to distinguish between them. Cuban culture encompasses a wide range of dance forms.  The island's indigenous people performed rituals known as areíto, which included dancing, although little information is known about such ceremonies.  After the colonization of Cuba by the Spanish Kingdom, European dance forms were introduced such as the French contredanse, which gave rise to the Cuban contradanza.  Contradanza itself spawned a series of ballroom dances between the 19th and 20th centuries, including the danzón, mambo and cha-cha-cha.  Rural dances of European origin, such as the zapateo and styles associated with punto guajiro also became established by the 19th century, and in the 20th century son became very popular.  In addition, numerous dance traditions were brought by black slaves from West Africa and the Congo basin, giving rise to religious dances such as Santería, yuka and abakuá, as well as secular forms such as rumba.  Many of these dance elements from European dance and religious dances were fused together to form the basis of la técnica cubana.  Cuban music also contributed to the emergence of Latin dance styles in the United States, namely rhumba (ballroom rumba) and salsa. A Coaster Step is term used in swing dances, in particular in West Coast Swing to describe a Triple Step done in the pattern "back-together-forward" or "forward-together-back".  Most often it is the follower's step.  As of 1994, the Coaster Step was still used in "Ballroom Swing", and is an identifying feature of that dance. 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: rumba, waltz, bronze-level foxtrot.  While it can be performed individually, it is usually done with a partner.  This is the most common dance step in the waltz.  In International Standard there is a similar step called Closed Change. Superior Dancing is a series of compilation CD albums dedicated to ballroom dances released by Kondor Musikvertrieb GmbH, Germany.  They contain music for International Style ballroom dances.
Answer: United States