Interfaces - Programming

Q1:

Which of the following statements are correct about an interface used in C#.NET?
  1. An interface can contain properties, methods and events.
  2. The keyword must implement forces implementation of an interface.
  3. Interfaces can be overloaded.
  4. Interfaces can be implemented by a class or a struct.
  5. Enhanced implementations of an interface can be developed without breaking existing code.

A 1, 2

B 1, 4, 5

C 3, 4

D 3 only

ANS:B - 1, 4, 5

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