How do Bots Answer Questions ?

There are simply too many technologies that really go into making a bot comprehend a question, then reason and finally respond to it. Unlike the human brain that has answers to most questions, intelligent systems have multiple answers to every question, it can comprehend and the cycle of responding with the right answer is often as key as being able to understand. This post is really about what kind of technologies and software architecture powers the QnA element of chatbots.