Question: when did the skeleton become an olympic sport
[{'answer': '1928', 'provenance': [{'wikipedia_id': '4230745', 'title': 'Skeleton at the Winter Olympics', 'start_paragraph_id': 1, 'start_character': 253, 'end_paragraph_id': 1, 'end_character': 257, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '4230745', 'title': 'Skeleton at the Winter Olympics', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 630, 'bleu_score': 0.9825310706027971, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11396513831735774980}, 'section': 'Section::::Abstract.'}]}]