lt;The concert having been finished and the audience having

A) The concert having been finished and the audience having filtered out, the maestro relaxed in the dressing room with the impresario.

B) Because the maestro had finished the concert and because the audience had been filtered out, he relaxed in the dressing room with the impresario.

C) Since the concert had been finished and the audience had filtered out, the maestro relaxed in the dressing room with the impresario.

D) Since the concert had finished and the audience had filtered out, the maestro had relaxed in the dressing room with the impresario.

E) The concert having been finished and the audience having filtered out, the maestro had relaxed in the dressing room with the impresario