着急，刘振民一道语法，请进welcome

The energy source on voyager 2 is not a nuclear reactor, im which atoms are actively broken apart ;rather a kind of nuclear battery that uses natural radioactive decay to produce power.

A  apart ; rather

B apart,  but rather

C apart, but rather that of

D apart, but that of

E apart ; it is that of

这道题目答案是B,

可是我在做的时候上来就排除了这个答案，我想but 是个连词，所以后面应该加句子才对。难道是句子的主谓省略了还是什么的原因，很迷惑啊！！请大家看看，谢谢发言了！！

not。。。。but rather 表示不是而是吧~我觉得