Question: where is white matter located in the brain
[{'answer': 'the Corpus callosum', 'provenance': [{'wikipedia_id': '33234', 'title': 'White matter', 'start_paragraph_id': 6, 'start_character': 276, 'end_paragraph_id': 6, 'end_character': 295, 'bleu_score': 1.0, 'section': 'Section::::Structure.:White matter.\n'}]}, {'provenance': [{'wikipedia_id': '33234', 'title': 'White matter', 'start_paragraph_id': 6, 'start_character': 0, 'end_paragraph_id': 6, 'end_character': 434, 'bleu_score': 0.893032352987798, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 8059359884956304606}, 'section': 'Section::::Structure.:White matter.\n'}]}]