Question: which allied nation dropped the atomic bomb on japan
[{'answer': 'the United States', 'provenance': [{'wikipedia_id': '2395137', 'title': 'Surrender of Japan', 'start_paragraph_id': 1, 'start_character': 359, 'end_paragraph_id': 1, 'end_character': 376, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2395137', 'title': 'Surrender of Japan', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 1173, 'bleu_score': 0.858059964542328, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16819995077670010890}, 'section': 'Section::::Abstract.'}]}]