Final answer:
Book publishing is the activity that is included in Ashley Incorporated's publishing industry operating segment, aligning with the core activities of publishing.
Step-by-step explanation:
When we look at Ashley Incorporated, which is specified as having a publishing industry operating segment, we need to consider activities closely related to the core processes of publishing. Among the options provided, book publishing is directly involved in the creation, marketing, and distribution of published materials, which aligns with the core activities of a publishing operating segment. In contrast, retail stores may sell books but their operation is not specific to the publishing process itself. Newspaper distribution is another form of publishing, but it is distinct from book publishing as it typically handles periodicals. Lastly, financial services are unrelated to the publishing industry and represent an entirely different financial sector.