C) How do I know which category to submit my textbook for sale under?
The listing of categories is simply used as a device to make browsing for textbooks more organized. However, it is not a big deal if you accidentally submit a textbook under the wrong sub-category. Most users will find the "search" function as the easiest way to find textbooks, so the category it is filed under is not necessarily very important. Entering its proper subject, class number, title, author, and/or ISBN, however, is.
