Question: where does the water come from that goes over victoria falls
[{'answer': 'Zambezi River', 'provenance': [{'wikipedia_id': '192485', 'title': 'Victoria Falls', 'start_paragraph_id': 1, 'start_character': 107, 'end_paragraph_id': 1, 'end_character': 120, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]