why is a classifier required here before newspapers?
I thought that the classifier would imply he is reading specific newspapers that happen to be important
It's true. However, one can say that there are only a number of specifically important newspapers (not all newspapers are important, I admit this sentence is weird).
If những is going to be required in the answer, shouldn't something indicating that be present in the English translation?
I was wondering about that. I was fooled by the Duolingo translation given for the English words newspapers that said "tò báo" was plural. I should have looked in my notes instead.