Question: the cavity in the shaft of a long bone is called the
[{'answer': 'medullary cavity', 'provenance': [{'wikipedia_id': '780913', 'title': 'Long bone', 'start_paragraph_id': 3, 'start_character': 227, 'end_paragraph_id': 3, 'end_character': 243, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '780913', 'title': 'Long bone', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 259, 'bleu_score': 0.955027111100031, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 12916667251472119924}, 'section': 'Section::::Abstract.'}]}]