69岁男性，咳嗽、胸闷、呼吸困难并大汗2h，无胸痛，2年前心电图提示有前间壁陈旧性心肌梗死，但患者既往无心前区疼痛病史，无高血压病史，平时不口服药物。查体：体温36．5℃，收缩压140mmHg，脉搏110／min，呼吸30／min，双肺布满湿啰音和哮鸣音。

最优先的检查为

A、心脏超声

B、胸片

C、心电图

D、心肌酶谱

E、肺动脉楔压监测

The recent upheaval in the office-equipment retail business, in which many small firms have gone out of business, has been attributed to the advent of office equipment "superstores" whose high sales volume keeps their prices low. This analysis is flawed, however, since even today the superstores control a very small share of the retail market.
Which of the following, if true, would most weaken the argument that the analysis is flawed

A．Most of the larger customers for office equipment purchase under contract directly from manufacturers and thus do not participate in the retail market.

B．The superstores’ heavy advertising of their low prices has forced prices down throughout the retail market for office supplies.

C．Some of the superstores that only recently opened have themselves gone out of business.

D．Most of the office equipment superstores are owned by large retailing chains that also own stores selling other types of goods.

E．(E) The growing importance of computers in most offices has changed the kind of office equipment retailers must stock.