ask og170 again

Although early soap operas were first aired on evening radio in the 1920's, they had moved to the daytime hours of the 1930's when the evening schedule became crowded with comedians and variety shows.

(A)  were first aired on evening radio in the 1920's, they had moved to the daytime hours of the 1930's

(B)   were first aired on evening radio in the 1920's, they were moved to the daytime hours in the 1930's

(C)  were aired first on evening radio in the 1920's, moving to the daytime hours in the 1930's

(D)  were aired first in the evening on 1920's radio, they moved to the daytime hours of the 1930's

(E)   aired on evening radio first in the 1920's, they were moved to the 1930's in the daytime hours

og explains that E drops were before aired and finishes the sentence with two prepositional phrases that distort the meaning.that means such a sentense is wrong:Although early soap operas first aired on evening radio in the 1920's, they had moved to the daytime hours of the 1930's when the evening schedule became crowded with comedians and variety shows.

the answer  is right,but if changed to :

Although first aired on evening radio in the 1920's, early soap operas were moved to the daytime hours of the 1930's when the evening schedule became crowded with comedians and variety shows.

i think such changes will be all right,to be discussed.

i think the use of although has two models

1.although modify the subject,such as the above changed sentense.

2.although  clause,main clause,the most impressive example is og 205.

to be discussed