good questions, also you may ask when Dispose method is calledDr Herbie wrote:"What is polymorphism and why is is useful?"
I was shocked at the number of candidates that couldn't separate polymorphism from class inheritance and I don't think I've met one yet who could explain why it was useful (other than inheriting functionality, which is not the correct answer).
Also, for C#, ask them to explain garbage collection.
Herbie