Question: what nations were the central powers in ww1
[{'answer': 'Germany', 'provenance': [{'wikipedia_id': '6673', 'title': 'Central Powers', 'start_paragraph_id': 1, 'start_character': 45, 'end_paragraph_id': 1, 'end_character': 52, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Austria - Hungary', 'provenance': [{'wikipedia_id': '6673', 'title': 'Central Powers', 'start_paragraph_id': 85, 'start_character': 434, 'end_paragraph_id': 85, 'end_character': 452, 'bleu_score': 1.0, 'section': 'Section::::Non-state combatants.\n'}]}, {'answer': 'Ottoman Empire', 'provenance': [{'wikipedia_id': '6673', 'title': 'Central Powers', 'start_paragraph_id': 1, 'start_character': 60, 'end_paragraph_id': 1, 'end_character': 74, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'Ottoman', 'provenance': [{'wikipedia_id': '6673', 'title': 'Central Powers', 'start_paragraph_id': 1, 'start_character': 60, 'end_paragraph_id': 1, 'end_character': 67, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '6673', 'title': 'Central Powers', 'start_paragraph_id': 2, 'start_character': 0, 'end_paragraph_id': 2, 'end_character': 517, 'bleu_score': 0.5256241741681851, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10830597259766728750}, 'section': 'Section::::Abstract.'}]}]