单选题Given the following code： public class Person{ int arr[] = new int[10]； public static void main（String a[]） { System.out.println（arr[1]）； } } Which statement is correct？（）A When compilation some error will occur.B It is correct when compilation but will cause error when running.C The output is zero.D The output is null.
单选题
Given the following code： public class Person{ int arr[] = new int[10]； public static void main（String a[]） { System.out.println（arr[1]）； } } Which statement is correct？（）
A
When compilation some error will occur.
B
It is correct when compilation but will cause error when running.
C
The output is zero.
D
The output is null.
参考解析
解析：
实例变量在类的一个实例构造时完成初始化，而且在类的静态方法中不能直接访问类的非静态成员而只能访问类成员（像上题中一样），类的普通方法可以访问类的所有成员和方法，而静态方法只能访问类的静态成员和方法，因为静态方法属于类，而普通方法及成员变量属于类的实例，类方法（静态方法）不能使用属于某个不确定的类的实例的方法和变量，在静态方法里面没有隐含的this，而普通方法有。
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