Anna R. answered 11d
Certified Teacher w/ 12 yrs of Elem Educ Experience-all subjects!
Hi!
I would say that you are correct in thinking that it modifies "Winnie the Pooh". I believe it modifies this noun because it tells WHAT the writing is about. If the prepositional phrase told HOW or WHEN it was written (e.g. "in 1926"), then it would modify the verb.
Let me know if you have any other questions! :)