Which of the following statements is true in terms of the relationship between sales and production of a product
选项：

A:Normally, the sales is quite high when a product is just introduced into the market.
B:The sales, sometime, is decreasing steadilybecausethe product is replaced by a new one.
C:The sales fall abruptly if the product is no longer popular in the market.
D:The sales usually increases quickly in the stage of market growth.