品牌的核心竞争力具备的主要特征有（）。
A.排他性
B.可持续性
C.执行力
D.感召力
E.关联性
参考答案：A, B, C, D
176. --- I didn’t know you were good friends.
--- You ______. I have known her since she moved here. You were studying aboard then.
A．may have
B．needn’t have
C．wouldn’t have
D．must have
诊断十二指肠溃疡的可靠x线征象是（ ）
A．十二指肠球部变形
B．十二指肠球部激惹
C．十二指肠球部压痛
D．十二指肠球部浓钡影
E．十二指肠球部狭窄梗阻
