Question: when did the queen became queen of england
[{'answer': '6 February 1952', 'provenance': [{'wikipedia_id': '12153654', 'title': 'Elizabeth II', 'start_paragraph_id': 27, 'start_character': 429, 'end_paragraph_id': 27, 'end_character': 444, 'bleu_score': 1.0, 'section': 'Section::::Reign.:Accession and coronation.\n'}]}]