169-When studying the origin of written language, one should

169-When studying the origin of written language, one should not overlook the demand for written law that developed at the same time as the organization of cities.


A. that developed at the same time as the organization of cities
B. that had developed at the same time as had the organization of cities
C. that developed at the same time as the organization of cities had
D. developing at the same time as the organization of cities did
E. developing at the same time as the organization of cities were

By POE I came to
we require that as 'that' depicts an extension of the information about the written law , hence D & E out
we don't require past perfect, no such comparison where some action occurred earlier than other so eliminate B & C
Hence A

Now even in A , I thing there are problems.
First after that there should be an auxiliary verb ; law can't develop by its own...
Anyway A is the best among worst

What is the source?

can someone explain?
I am not able to get the comparison in A with the 'same time as'.