Task: Text Categorization
Input (English): Iannis Xenakis used eight so-called "sound complexes" in a solo work for this instrument called Nomos Alpha. Six beats on the body of these instruments begin the main theme in Arvo Part's orchestration of Fratres for twelve of them. An ensemble consisting entirely of these instruments was founded in the 1970s by twelve members of the Berlin Philharmonic. The first of Villa-Lobos's Bachianas Brasileiras was composed for (*) eight of these instruments, while Jacqueline du Pre popularized Edward Elgar's concerto for it. J.S. Bach's six unaccompanied suites for this instrument were famously recorded by both Mstislav Rostropovich and Pablo Casals. For 10 points, name this instrument played by Yo-Yo Ma which joins two violins and a viola in a string quartet.
Output (English): Fine Arts