Question: who sang backing vocals on the nine inch nails song survivalism
[{'answer': 'Saul Williams', 'provenance': [{'wikipedia_id': '9242711', 'title': 'Survivalism (song)', 'start_paragraph_id': 31, 'start_character': 12, 'end_paragraph_id': 31, 'end_character': 25, 'bleu_score': 1.0, 'section': 'Section::::Credits and personnel.:"Survivalism".\n'}]}]