Question: where is cardiac muscle tissue located in the body
[{'answer': 'heart', 'provenance': [{'wikipedia_id': '424348', 'title': 'Cardiac muscle', 'start_paragraph_id': 1, 'start_character': 28, 'end_paragraph_id': 1, 'end_character': 33, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]