代词的指代对象不能出现在定语成分中”，这对吗？

“代词的指代对象不能出现在定语成分中”，这对吗？

80. Salt deposits and moisture threaten to destroy the Mohenjo-Daro excavation in Pakistan, the site of an ancient civilization that flourished at the same time as the civilizations in the Nile delta and the river valleys of the Tigris and Euphrates.

(A)  that flourished at the same time as the civilizations

(B)  that had flourished at the same time as had the civilizations

(C)  that flourished at the same time ？ those had

(D)  flourishing at the same time as those did

(E)   flourishing at the same time as those were

此题中的abc不就是指代site的定语civilization了吗？这不是违反了“代词的指代对象不能出现在定语成分中”吗？

请nn指教！！！