Question: where does most cape towns water supply come from
[{'answer': 'the Sonderend River', 'provenance': [{'wikipedia_id': '25423530', 'title': 'Western Cape Water Supply System', 'start_paragraph_id': 3, 'start_character': 172, 'end_paragraph_id': 3, 'end_character': 191, 'bleu_score': 1.0, 'section': 'Section::::Components.\n'}]}, {'answer': 'the Berg River', 'provenance': [{'wikipedia_id': '25423530', 'title': 'Western Cape Water Supply System', 'start_paragraph_id': 3, 'start_character': 232, 'end_paragraph_id': 3, 'end_character': 246, 'bleu_score': 1.0, 'section': 'Section::::Components.\n'}]}, {'answer': 'Eerste River', 'provenance': [{'wikipedia_id': '25423530', 'title': 'Western Cape Water Supply System', 'start_paragraph_id': 3, 'start_character': 292, 'end_paragraph_id': 3, 'end_character': 304, 'bleu_score': 1.0, 'section': 'Section::::Components.\n'}]}, {'provenance': [{'wikipedia_id': '25423530', 'title': 'Western Cape Water Supply System', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 330, 'bleu_score': 0.915132941383415, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 7216328935629193758}, 'section': 'Section::::Components.\n'}]}]