I voted Other because this pool doesn't have multiple choices !
My native language is french, and I restarted reading in english (after school) for work : I needed to read books and publications that were in english only.
So to improve my english I began to read books in that language when they were written initially in english.
Now I wouldn't purchase a book in english if it's a french one initially, but I purchased some others in english because they weren't available in french on ebook format for a reasonable price (or at all !)
Then with a multiple choices pool I would have voted, 2+3+4...