Question: who has won the most mvp in nba history
[{'answer': 'Kareem Abdul - Jabbar', 'provenance': [{'wikipedia_id': '631870', 'title': 'NBA Most Valuable Player Award', 'start_paragraph_id': 3, 'start_character': 127, 'end_paragraph_id': 3, 'end_character': 150, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '631870', 'title': 'NBA Most Valuable Player Award', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 872, 'bleu_score': 0.7949178750201601, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6318212690877460881}, 'section': 'Section::::Abstract.'}]}]