Question: what was the cause of the nigerian civil war
[{'answer': 'a military coup', 'provenance': [{'wikipedia_id': '632165', 'title': 'Nigerian Civil War', 'start_paragraph_id': 1, 'start_character': 623, 'end_paragraph_id': 1, 'end_character': 638, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'a counter-coup', 'provenance': [{'wikipedia_id': '632165', 'title': 'Nigerian Civil War', 'start_paragraph_id': 1, 'start_character': 640, 'end_paragraph_id': 1, 'end_character': 654, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'persecution of Igbo', 'provenance': [{'wikipedia_id': '632165', 'title': 'Nigerian Civil War', 'start_paragraph_id': 1, 'start_character': 659, 'end_paragraph_id': 1, 'end_character': 678, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '632165', 'title': 'Nigerian Civil War', 'start_paragraph_id': 1, 'start_character': 54, 'end_paragraph_id': 1, 'end_character': 797, 'bleu_score': 0.8609339845451041, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 6019482744732319486}, 'section': 'Section::::Abstract.'}]}]