Angina pectoris, a type of chest pain, is a feeling of constriction around the heart or pain that may radiate to the left arm or shoulder, usually brought on by exertion.
【正确答案】 A
【答案解析】解析：constriction“紧缩，压缩”。contraction“收缩，(分娩时)子宫收缩”；constraint“强制，限制，约束”；contribution“贡献，捐赠，捐助”：constitution“建立，组成”。根据句意，心绞痛时，胸前区应该是有紧缩感，应选“紧缩”的同义词，故选A。