Question: what age can you buy alcohol in usa
[{'answer': '21', 'provenance': [{'wikipedia_id': '1015583', 'title': 'Legal drinking age', 'start_paragraph_id': 5, 'start_character': 469, 'end_paragraph_id': 5, 'end_character': 471, 'bleu_score': 1.0, 'section': 'Section::::Africa.\n'}]}]