We have worked for such a long time. Shall we stop _______ a rest? [ ]

A. having

B. to have

C. have

D. had

男性，72岁，因持续胸痛6小时入院，查体双肺底有少量湿啰音，诊断为急性心肌梗死，该患者心功能分级为（）。

A.NYHA分级Ⅰ级

B.NYHA分级Ⅳ级

C.NYHA分级Ⅱ级

D.Killp分级为Ⅱ级

E.Killp分级为Ⅲ级