Are these your scissors? Yes, ___________.[ ]
A. they are
B. it is
C. I am
答案：A
_____ the three elements of productive forces, namely, the people, the means of production and the subject of labor, the people is that most critical.
A．From
B．With
C．For
D．Of
男性，56岁，吸烟20支／天，一年来反复发作胸骨后疼痛，持续10～15分钟，发作与劳力无关，常于凌晨发作，含服硝酸甘油可使疼痛缓解。休息时心电图正常。最近一次发作时心电图呈V1～V4导联ST段抬高，Ⅱ、Ⅲ、aVF导联ST段压低，发作后恢复正常。可能的诊断是（）
A.恶化型劳力性心绞痛
B.急性心肌梗死
C.变异型心绞痛
D.心绞痛合并急性心包炎
E.卧位型心绞痛
