Question: who was involved in the washington naval conference
[{'answer': 'United States', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 352, 'end_paragraph_id': 1, 'end_character': 365, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Japan', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 367, 'end_paragraph_id': 1, 'end_character': 372, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'China', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 374, 'end_paragraph_id': 1, 'end_character': 379, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'France', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 381, 'end_paragraph_id': 1, 'end_character': 387, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Britain', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 389, 'end_paragraph_id': 1, 'end_character': 396, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Italy', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 398, 'end_paragraph_id': 1, 'end_character': 403, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Belgium', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 405, 'end_paragraph_id': 1, 'end_character': 412, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Netherlands', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 414, 'end_paragraph_id': 1, 'end_character': 425, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Portugal', 'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 431, 'end_paragraph_id': 1, 'end_character': 439, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '703152', 'title': 'Washington Naval Conference', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 712, 'bleu_score': 0.8783790986507021, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9740676279820308397}, 'section': 'Section::::Abstract.'}]}]