Question: where is the left anterior descending artery located
[{'answer': 'the left coronary artery', 'provenance': [{'wikipedia_id': '7193171', 'title': 'Left anterior descending artery', 'start_paragraph_id': 1, 'start_character': 151, 'end_paragraph_id': 1, 'end_character': 175, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '7193171', 'title': 'Left anterior descending artery', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 209, 'bleu_score': 0.943604326170661, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10722439128935314448}, 'section': 'Section::::Structure.\n'}]}, {'provenance': [{'wikipedia_id': '7193171', 'title': 'Left anterior descending artery', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 271, 'bleu_score': 0.8330622053723671, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 10722439128935314448}, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '2580767', 'title': 'Left coronary artery', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['The left coronary artery (abbreviated LCA) is an artery that arises from the aorta above the left cusp of the aortic valve and feeds blood to the left side of the heart. It is also known as the left main coronary artery (abbreviated LMCA) and the left main stem coronary artery (abbreviated LMS). It is one of the coronary arteries.', 'The left coronary artery (abbreviated LCA) is an artery that arises from the aorta above the left cusp of the aortic valve and feeds blood to the left side of the heart', 'The left coronary artery (abbreviated LCA) is an artery that arises from the aorta above the left cusp of the aortic valve and feeds blood to the left side of the heart. It is also known as the left main coronary artery (abbreviated LMCA) and the left main stem coronary artery (abbreviated LMS). It is one of the coronary arteries.']}}]}, {'provenance': [{'wikipedia_id': '7193171', 'title': 'Left anterior descending artery', 'section': 'Section::::Abstract.', 'start_paragraph_id': 1, 'end_paragraph_id': 1, 'meta': {'evidence_span': ['The left anterior descending artery (also LAD, anterior interventricular branch of left coronary artery, or anterior descending branch) is a branch of the left coronary artery. Occlusion of this artery is often called the "widow-maker infarction" due to a high death risk.', 'The left anterior descending artery (also LAD, anterior interventricular branch of left coronary artery, or anterior descending branch) is a branch of the left coronary artery.', 'The left anterior descending artery (also LAD, anterior interventricular branch of left coronary artery, or anterior descending branch) is a branch of the left coronary artery. Occlusion of this artery is often called the "widow-maker infarction" due to a high death risk.']}}]}, {'provenance': [{'wikipedia_id': '146642', 'title': 'Coronary circulation', 'section': 'Section::::Structure.\n', 'start_paragraph_id': 6, 'end_paragraph_id': 6, 'meta': {'evidence_span': ['Coronary arteries supply blood to the myocardium and other components of the heart. Two coronary arteries originate from the left side of the heart at the beginning (root) of the aorta, just after the aorta exits the left ventricle. There are three aortic sinuses (dilations) in the wall of the aorta just superior to the aortic semilunar valve. Two of these, the left posterior aortic sinus and anterior aortic sinus, give rise to the left and right coronary arteries, respectively. The third sinus, the right posterior aortic sinus, typically does not give rise to a vessel. Coronary vessel branches that remain on the surface of the artery and follow the sulci of the heart are called "epicardial" coronary arteries.', 'Coronary arteries supply blood to the myocardium and other components of the heart. Two coronary arteries originate from the left side of the heart at the beginning (root) of the aorta, just after the aorta exits the left ventricle. There are three aortic sinuses (dilations) in the wall of the aorta just superior to the aortic semilunar valve. Two of these, the left posterior aortic sinus and anterior aortic sinus, give rise to the left and right coronary arteries, respectively. The third sinus, the right posterior aortic sinus, typically does not give rise to a vessel. Coronary vessel branches that remain on the surface of the artery and follow the sulci of the heart are called "epicardial" coronary arteries.']}}]}]