Question: what does mc mean on a biker vest
[{'answer': 'motorcycle club', 'provenance': [{'wikipedia_id': '876181', 'title': 'Motorcycle club', 'start_paragraph_id': 1, 'start_character': 2, 'end_paragraph_id': 1, 'end_character': 17, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '876181', 'title': 'Motorcycle club', 'start_paragraph_id': 13, 'start_character': 0, 'end_paragraph_id': 13, 'end_character': 991, 'bleu_score': 0.9879148529393721, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17821708166668556231}, 'section': 'Section::::MCs and MCCs.\n'}]}]