Question: black shield in nigeria coat of arm represent what
[{'answer': "Nigeria 's fertile soil", 'provenance': [{'wikipedia_id': '3037029', 'title': 'Coat of arms of Nigeria', 'start_paragraph_id': 1, 'start_character': 172, 'end_paragraph_id': 1, 'end_character': 195, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '3037029', 'title': 'Coat of arms of Nigeria', 'start_paragraph_id': 1, 'start_character': 28, 'end_paragraph_id': 1, 'end_character': 383, 'bleu_score': 0.662682031296545, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14479157401515144666}, 'section': 'Section::::Abstract.'}]}]