WCDMA中，以下哪个接口开放可以促使不同厂商的NodeB可以与不同厂商的RNC相连接：（）
A.Iu
B.Iur
C.Iub
D.Abis
参考答案：C
As _______ unemployment is very high at the moment, it’s very difficult for people to find _______ work.
A．the, 不填
B．不填，不填
C．the, a
D．an, the
