Question: what was the highest category of hurricane katrina
[{'answer': 'Category 5', 'provenance': [{'wikipedia_id': '2569378', 'title': 'Hurricane Katrina', 'start_paragraph_id': 1, 'start_character': 58, 'end_paragraph_id': 1, 'end_character': 68, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2569378', 'title': 'Hurricane Katrina', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 729, 'bleu_score': 0.7486228638158581, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5579434773380542686}, 'section': 'Section::::Abstract.'}]}]