public class Person {  private name；  public Person（String name） {  this.name = name；  }  public boolean equals（Object o） {  if（ !o instanceof Person ） return false；  Person p = （Person） o；  return p.name.equals（this.name）；  }  }  Which is true？（） 

A、 Compilation fails because the hashCode method is not overridden.

B、 A HashSet could contain multiple Person objects with the same name.

C、 All Person objects will have the same hash code because the hashCode method is not overridden.

D、 If a HashSet contains more than one Person object with name=”Fred”， then removing another person， also with name=”Fred”， will remove them all.

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