Sept répons des ténèbres was composed by a pianist whose work includes what 1957 opera?
Francis Poulenc:  Among the best-known are the piano suite "Trois mouvements perpétuels" (1919), the ballet "Les biches" (1923), the "Concert champêtre" (1928) for harpsichord and orchestra, the Organ Concerto (1938), the opera "Dialogues des Carmélites" (1957), and the "Gloria" (1959) for soprano, choir and orchestra.
i don't know