炒菜时，加一点酒和醋能使菜味香可口，原因是生成了

A．酸类物质

B．醇类物质

C．酯类物质

D．盐类物质

Having finished lunch, the case was discussed.()

A. they discussed the case

B. they had discussed the case

C. the case was discussed

D. the case had been discussed