Consumer porcelains in Jingdezhen are not selling well in export market as compared with those made in Liling, Hunan Province and Zibo, Shandong Province.

A．on export market

B．in exporting market

C．in exported market

D．in the export market

煤气燃烧可分为（）方式。

A.自然燃烧

B.动力燃烧

C.扩散燃烧

D.爆炸燃烧