The answer is B.2
because the words in that sentence don't have any positive or negative connotations. expressed is just signalizing that they were debating over a topic.
1. an entry in the catalog listed under the topic or subject of the book - subject entry
2. a listing of books in a library - catalog system
3. an entry in the catalog listed by the author's name - author entry
4. an entry in the catalog listed under the title of the book - title entry