Question: what family is the rhubarb a part of
[{'answer': 'Polygonaceae', 'provenance': [{'wikipedia_id': '56277', 'title': 'Rhubarb', 'start_paragraph_id': 1, 'start_character': 65, 'end_paragraph_id': 1, 'end_character': 77, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]