多选题现有:  class ClassA  {}  class ClassB extends ClassA  {)      class ClassC extends ClassA  {)     以及:  ClassA p0=new ClassA();      ClassB pl=new ClassB();      ClassC p2=new ClassC();     ClassA p3=new ClassB();    ClassA p4=new ClassC(); 下列哪些是正确的?()Ap0=pl;Bp1 =p2;Cp2=p4;Dp2 = (ClassC)pl;Ep1 = (ClassB)p3;Fp2 =  (Classc)p4;

多选题
现有:  class ClassA  {}  class ClassB extends ClassA  {)      class ClassC extends ClassA  {)     以及:  ClassA p0=new ClassA();      ClassB pl=new ClassB();      ClassC p2=new ClassC();     ClassA p3=new ClassB();    ClassA p4=new ClassC(); 下列哪些是正确的?()
A

p0=pl;

B

p1 =p2;

C

p2=p4;

D

p2 = (ClassC)pl;

E

p1 = (ClassB)p3;

F

p2 =  (Classc)p4;


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