程序: class TestReference{ public static void main(String[] args){ int x=2; TestReference tr = new TestReference(); System.out.print(x); tr.change(x); System.out.print(x); } public void change(int num){ num = num + 1; } } 程序运行后的输出是哪项?()
- A 23
- B 21
- C 22
- D 编译错误