Question: what is the most famous fountain in rome
[{'answer': 'Trevi Fountain', 'provenance': [{'wikipedia_id': '335740', 'title': 'Trevi Fountain', 'start_paragraph_id': 0, 'start_character': 0, 'end_paragraph_id': 0, 'end_character': 14, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '335740', 'title': 'Trevi Fountain', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 476, 'bleu_score': 0.679605063754756, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10918990782776491679}, 'section': 'Section::::Abstract.'}]}]