Question: area of land drained by a single river
[{'answer': 'drainage basin', 'provenance': [{'wikipedia_id': '191162', 'title': 'Drainage basin', 'start_paragraph_id': 1, 'start_character': 2, 'end_paragraph_id': 1, 'end_character': 16, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '191162', 'title': 'Drainage basin', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 534, 'bleu_score': 0.899857788642431, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14949153528183824422}, 'section': 'Section::::Abstract.'}]}]