—Excuse me. Where is the cafe ?

—Take the elevator _____ the third floor and turn left. And it is _____the bank and the bookstore.

A．at; between

B．at; next to

C．to; next to

D．to; between

只有单一模式传输的光纤称做（）光纤。

A.单模

B.多模

C.单波

D.多波