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Casaer was played by a woman ( the part was written for a castrato , except they do n't castrate people anymore , so they have to use women instead ) , which was interesting to see . Also , there was a fairly small ensemble accompanying the singers , so there were no walls of sounds or great impressive fanfares . But the music was good .

Question:
What may I have just seen ?
OPT: a). A rock show; b). A opera; c). None of the above choices .; d). A play;