请教prep上的一个语法题

bdx2010

57.   (答案是B我选了D，请NN指教，非常感谢)

 

The Anasazi settlements at Chaco Canyon were built on a spectacular scale with more than 75 carefully engineered structures, of up to 600 rooms each, were connected by a complex regional system of roads.

 

(A) with more than 75 carefully engineered structures, of up to 600 rooms each, were

(B) with more than 75 carefully engineered structures, of up to 600 rooms each,

(C) of more than 75 carefully engineered structures of up to 600 rooms, each that had been

(D) of more than 75 carefully engineered structures of up to 600 rooms and with each

(E) of more than 75 carefully engineered structures of up to 600 rooms each had been

bdx2010

来帮帮忙嘛

freelaneliu

建议你自己搜一下prep语法笔记，这道题讲的非常清楚！