Question: which tribe has the highest population in nigeria
[{'answer': 'the Hausa / Fulani'}, {'provenance': [{'wikipedia_id': '21386', 'title': 'Demographics of Nigeria', 'start_paragraph_id': 1, 'start_character': 186, 'end_paragraph_id': 1, 'end_character': 770, 'bleu_score': 0.8338384293180011, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 5666023934218970280}, 'section': 'Section::::Abstract.'}]}]