Question: what is the largest county in population in tennessee
[{'answer': 'Shelby County', 'provenance': [{'wikipedia_id': '23508479', 'title': 'List of counties in Tennessee', 'start_paragraph_id': 2, 'start_character': 12, 'end_paragraph_id': 2, 'end_character': 25, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '23508479', 'title': 'List of counties in Tennessee', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 581, 'bleu_score': 0.720896890022477, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15801594496506765597}, 'section': 'Section::::Abstract.'}]}]