OG12-1

1.The glass house mountains in queensland ,Australia,were sighted in 1770 by the English navigator Captain James Cook ,by whom they were named supposedly because its sheer wet rocks glisteded like glass.

A:by whom they were named supposedly because its

B:by whom they were named supposedly and their

C:naming them supposedly since their

D:who so  named them supposedly because their

E:who so  named it since  supposedly  their

这道题的c选项那里错了呢？

谢谢