I'm going to the beach              I enjoy             . [ ]

A. so; swiming

B. and; swims

C. or; to swim

D. because; swimming

插入肺动脉漂浮导管时最容易出现危险的是导管（）。

A.到达上腔静脉和右心房交界处时

B.到达右心房时

C.到达右心房和右心室交界处时

D.到达右心室时

E.到达肺动脉时