What is the best choice in this case past continuous or simple

Question

While she was driving to work every day she was listening or listened to languages CDs

In the test the answer is listened because the action is completed now: she does not listen to these cds anymore but she is still driving to work

Could was listening be ok because at this time she was still listening to these cds even if now the action is finished

The complete exercise can be found here

Answer 1

Past continuous can be used for two actions happening at the same time, so called parallel actions. More information about past continuous here.