菜鸟问一道语法题~

Carbon-14 dating reveals that the megalithic monuments in Brittany are nearly 2,000 years as old as any of their supposed Mediterranean predecessors.

(A)  as old as any of their supposed

(B)  older than any of their supposed

(C)  as old as their supposed

(D)  older than any of their supposedly

(E)   as old as their supposedly

请问怎么看出monuments和their supposed predecessors是比较的意思，为什么as old as 不行呢？

要从整句话的意思来看，在这个比较前有nearly 2,000 years，不能用平级，只能用比较级，否则逻辑意思就不对了

谢谢楼上TX,俺又想出两点来支持用比较结构：1、Carbon-14揭露的应该是真实情况，而predecessors是supposed的，不是真实情况，所以两者年龄不能相等，只能比较。2、句子中有个2000years,如果说两种东西年龄相等直接用as old as 就可以，没必要加一个具体的时间。因此有这个2000years只能说明是比较。

请各位DX们指教！