Question: what is the widest highway in north america
[{'answer': 'Highway 401', 'provenance': [{'wikipedia_id': '291924', 'title': 'Ontario Highway 401', 'start_paragraph_id': 0, 'start_character': 8, 'end_paragraph_id': 0, 'end_character': 19, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]