Class question "Can you allow a class to be inherited, but prevent the method from being over-ridden?" answer (Yes. Just leave the class public and make the method sealed.) is wrong. You cannot use the "sealed" modifier in a public class that is not over-riding the class that implements the method or property that you want to seal. If you want to stop someone from over-riding a method or property just do not add the "virtual" modifier to it

The following will raise an error. If you switched the GetPerson in the Person class to include the "virtual" modifier then it would work.
public class Person{
public string GetPerson(){

}
}
public class Member: Person{
override public string GetPerson(){
}
}