Question: who won americas next top model cycle 21
[{'answer': 'Keith Carlos', 'provenance': [{'wikipedia_id': '41959891', 'title': "America's Next Top Model (season 21)", 'start_paragraph_id': 3, 'start_character': 46, 'end_paragraph_id': 3, 'end_character': 58, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]