單項(xiàng)選擇題COPD患者肺功能回報(bào):FEV1/FVC<60%,F(xiàn)EV1/預(yù)計(jì)值:45%,患者PO250mmHg,PCO266mmHg,該患者按COPD嚴(yán)重程度分級(jí)屬于()

A.輕度COPD
B.中度COPD
C.重度COPD
D.極重度COPD
E.高危COPD