Question: who has the highest on base percentage of all time
[{'answer': 'Barry Bonds', 'provenance': [{'wikipedia_id': '12891584', 'title': 'List of Major League Baseball career on-base percentage leaders', 'start_paragraph_id': 1, 'start_character': 886, 'end_paragraph_id': 1, 'end_character': 897, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '12891584', 'title': 'List of Major League Baseball career on-base percentage leaders', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 1207, 'bleu_score': 0.9908043535876511, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 1897138866750457810}, 'section': 'Section::::Abstract.'}]}]