Question: who has played in the most world series
[{'answer': 'New York Yankees', 'provenance': [{'wikipedia_id': '23489161', 'title': 'World Series', 'start_paragraph_id': 4, 'start_character': 28, 'end_paragraph_id': 4, 'end_character': 44, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '23489161', 'title': 'World Series', 'start_paragraph_id': 4, 'start_character': 0, 'end_paragraph_id': 4, 'end_character': 509, 'bleu_score': 0.9096083227075611, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15813916125194426177}, 'section': 'Section::::Abstract.'}]}]