The committee, consisted by the advisor and several other professors from the same department, asked the basic questions in my major, as well as other questions, like why do you choose our school et al.

They're just looking to see if you're lying on your resume and making sure you're not crazy. If they're interviewing you, you're probably going to get in unless you say something moronic or can't actively discuss what you've put on your resume. Don't make stuff up and don't be crazy. The more boring and results focused you are, the better.