There are four bookstores in A. B, and D in one city. Among them, all books in A and B can be found in B and B. Books sold in B and B must also be sold in C and B. Some books in C and B are also sold in D. It can be inferred from this:. ['Some books in A bookstore can be found in B bookstore.', 'Some books in B Bookstore can be found in Ding Bookstore.', 'All the books in Ding Bookstore can be found in B Bookstore.', 'All books in Bookstore A can be found in Bookstore C.']