—What’s the low-carbon (低碳的) lifestyle like?

—Save ___________ energy, produce ___________ carbon.

A. less; more            B. less; less             C. more; less

下列哪项是肺动脉瓣狭窄的并发症：（）

A.缺氧发作

B.细菌性心内膜炎

C.肺炎

D.脑脓肿

E.脑血管血栓