Question: when did table tennis become an olympic sport
[{'answer': '1988', 'provenance': [{'wikipedia_id': '6085499', 'title': 'Table tennis at the Summer Olympics', 'start_paragraph_id': 1, 'start_character': 68, 'end_paragraph_id': 1, 'end_character': 72, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '6085499', 'title': 'Table tennis at the Summer Olympics', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 371, 'bleu_score': 0.970362113628587, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4400536119554811995}, 'section': 'Section::::Abstract.'}]}]