A.When the readers make pre-orders.
B.When the publishers have not enough stock of certain books.
C.When this kind of book is very popular in the market.
D.When the copies the publishers offered are of poor qualities.
A.The publishers should offer copies at a very low price.
B.The books offered by the publishers must be of good quality.
C.The publisher should offer Amazon the same promotions as it offers to distributors.
D.The publishers should inform Amazon if it offers books to its clients.