title: What do you use if you want to ensure that all methods and properties are implemented
body: <p>I was giving a test and got one question.
  QUESTION:
  What do you use if you want to ensure that all methods and properties are implemented?
  a)Inheritance.
  b)Polymorphism.
  c)Encapsulation
  d)Interface.</p>
  
  <p>I think its Interface. Am I right or the. ans is diff?</p>