Question: who is the lead singer of the group disturbed
[{'answer': 'David Michael Draiman', 'provenance': [{'wikipedia_id': '1645902', 'title': 'David Draiman', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 21, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '1645902', 'title': 'David Draiman', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 502, 'bleu_score': 0.7692691276009801, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4423046502341902817}, 'section': 'Section::::Abstract.'}]}]