单选题public class Pet{} public class Cat extends Pet{} 执行代码 Cat c = new Cat(); Pet p = (Pet)c; 下列哪项是正确的?APet p = (Pet)c正常执行BPet p = (Pet)c编译错误CPet p = (Pet)c运行错误D以上都不对
单选题
public class Pet{} public class Cat extends Pet{} 执行代码 Cat c = new Cat(); Pet p = (Pet)c; 下列哪项是正确的?
A
Pet p = (Pet)c正常执行
B
Pet p = (Pet)c编译错误
C
Pet p = (Pet)c运行错误
D
以上都不对
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