Question: where are sister chromatids attached to one another
[{'answer': 'a common centromere', 'provenance': [{'wikipedia_id': '4215206', 'title': 'Sister chromatids', 'start_paragraph_id': 1, 'start_character': 146, 'end_paragraph_id': 1, 'end_character': 165, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '4215206', 'title': 'Sister chromatids', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 588, 'bleu_score': 0.9642618757124931, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5923656213081922671}, 'section': 'Section::::Abstract.'}]}]