Given the following code, find the compile error. ( )Public class Test {Public static void main(String] args) {M(new GraduateStudent());M(new Student());M(new Person());M(new Object());}Public static void m(Student x) {System.out.println(x.toString());}}Class GraduateStudent extends Student {}Class Student extends Person {@OverridePublic String toString() {Return "Student";}}Class Person extends Object {@OverridePublic String toString() {Return "Person";} }
选项：

A:m(new GraduateStudent()) causes an error
B:m(new Student()) causes an error
C:m(new Person()) causes an error
D:m(new Object()) causes an error