The most popular organic gem is the pearl. A pearl is the response of a marine mollusk to the presence of an irritating impurity accidentally introduced into its body; a cultured pearl is the result of the intentional insertion of a mother-of-pearl bead into a live mollusk. Whether introduced accidentally or intentionally, the pearl-making process is the same: the mollusk coats the irritant with a substance called nacre. Nacre is composed chiefly of calcium carbonate. Because very few natural pearls are now on the market, most pearls used in fine jewelry are cultured. These include "Biwa" pearls and most other freshwater pearls. Cultured pearls are not easily distinguished from natural pearls except by an expert.

Which of the following people could tell the difference between a cultured pearl and an organic pearl

A．Scuba diver.

B．Fisherman.

C．Jeweler.

D．Clerk.

考生文件夹下有一个数据库文件“samp2.mdb”，其中存在已经设计好的一个表对象“tBook，请按以下要求完成设计。

创建一个查询，按出版社名称查找某出版社的图书信息，并显示图书的“书名”、“类别”、“作者名”和“出版社名称”4个字段的内容。当运行该查询时，应显示参数提示信息：“请输入出版社名称：”，将查询命名为“qT3”。