[求助]新prep2-215，关于date的用法

Rock samples taken from the remains of an asteroid about twice the size of the 6-mile-wide asteroid that eradicated the dinosaurs has been dated to be 3.47 billion years old and thus is evidence of the earliest known asteroid impact on Earth.

A. has been dated to be 3.47 billion years old and thus is

B. has been dated at 3.47 billion years old and thus

C. have been dated to be 3.47 billion years old and thus are

D. have been dated as being 3.47 billion years old and thus

E. have been dated at 3.47 billion years old and thus are

想问C为什么不对呀？date怎么用？在LONGMAN上没查到。

都一天了，怎么都没人理我啊。。。55

Cambrige dictionary

date    

 to say how long something has existed or when it was made:
e.g.Archaeologists have been unable to date these fossils.
An antique dealer had dated the vase at (= said that it was made in) 1734.

so E