已知类的继承关系如下:class Employee;class Manager extends Employeer;class Director extends Employee;则以下语句能通过编译的有哪些? A.Employee e=new Manager();B.Director d=new Manager();C.Director d=new Employee();D.Manager m=new Director();
已知类的继承关系如下:class Employee;class Manager extends Employeer;class Director extends Employee;则以下语句能通过编译的有哪些?
A.Employee e=new Manager();
B.Director d=new Manager();
C.Director d=new Employee();
D.Manager m=new Director();
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