A 35-year-old client is undergoing a brain computed tomography (CT) scan because of continued migraine headaches. He’s placed in the CT scanner and suddenly begins to complain of palpitations, sweating, shortness of breath, and shaking. The client is most likely experiencing

A. an allergic reaction.
B. a myocardial infarction (MI).
C. a panic attack.
D. a hypoglycemic episod

网桥按照路由表的建立方法分为两类：______和源路由网桥。