—Do you know the colors of the Olympic rings?

—Yes. They're blue, yellow, black, green and red. You can find ____ one of these colors in the flags

    of every country. [ ]

A. at least

B. at most

C. only

D. more than

肝癌患者，平扫见肿瘤边缘更低密度环状带，增强扫描显示低密度环状带于门静脉期和实质期增强，提示多为肝癌的哪一型（）

A.巨块型

B.结节型

C.弥漫型

D.外生型

E.空洞型