Given:<br /> <img src="https://img.ppkao.com/2018-08/wenxueying/2018080115564592823.png" /><br /> What are four valid examples of polymorphic method calls?()<p> Given:<br /> <img src="https://img.ppkao.com/2018-08/wenxueying/2018080115564592823.png" /><br /> What are four valid examples of polymorphic method calls?()</p>
A、A.x.a2();
B、B.z.a2();
C、C.z.c1();
D、D.z.a1();
E、E.y.c1();
F、F.x.a1();