Question: who proposed the double helical model of dna
[{'answer': 'Francis Crick', 'provenance': [{'wikipedia_id': '7955', 'title': 'DNA', 'start_paragraph_id': 5, 'start_character': 102, 'end_paragraph_id': 5, 'end_character': 115, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'answer': 'James Watson', 'provenance': [{'wikipedia_id': '7955', 'title': 'DNA', 'start_paragraph_id': 5, 'start_character': 120, 'end_paragraph_id': 5, 'end_character': 132, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '7955', 'title': 'DNA', 'start_paragraph_id': 149, 'start_character': 0, 'end_paragraph_id': 149, 'end_character': 641, 'bleu_score': 0.9579655027162681, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 11116842945646367944}, 'section': 'Section::::History.\n'}]}]