假设已经定义好了类student，现在要定义类derived,它是从student私有派生的，则定义类derived的正确写法是

假设已经定义好了类student，现在要定义类derived,它是从student私有派生的，则定义类derived的正确写法是

A.class derived：student private{ //............}

B.class derived：student public { //............}

C.class derived：public student { //............}

D.class derived：private student{ //...........}

正确答案是D