Question: who sings the voice of elsa in frozen
[{'answer': 'Idina Menzel', 'provenance': [{'wikipedia_id': '41312390', 'title': 'Elsa (Frozen)', 'start_paragraph_id': 1, 'start_character': 206, 'end_paragraph_id': 1, 'end_character': 218, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '41312390', 'title': 'Elsa (Frozen)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 314, 'bleu_score': 0.796262798967558, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 16696847213174315486}, 'section': 'Section::::Abstract.'}]}]