Sometimes she talks with Mary over ________ telephone，that is to say，they keep in touch with each other by ________ telephone.

A．the；/

B．/；/

C．/；the

D．the；the

有只猴子在树林采了100根香蕉堆成一堆，猴子家离香蕉堆50米，猴子打算把香蕉背回家，每次最多能背50根，可是猴子嘴馋，每走一米要吃一根香蕉，猴子最多能背回家[ ]

A．0根

B．25根

C．50根

D．100根