关于英语定语从句.

问题描述:

关于英语定语从句.
Chang'e-l is a circumlunar satlllite ____ scientisits can conduct research on the moon
A.which
B.by which
C.for which
D.to which
介词+关系代词这里我实在是不晓得选哪个...

B
科学家用这个卫星.
这个是根据句子意思来的.