Be pragmatic and polite and don’t answer questions. If they ask you whether you know why they stopped you simply say “No, why?” (For the love of goodness, don’t admit that you were doing something wrong or even worse say you didn’t do anything wrong when you did.) If they ask you for ID provide them with one. It doesn’t seem that they would ask you any more questions, they can just hand you over the ticket. If they really do continue asking questions you can just politely say that you would rather not answer any more questions. That’s behavior very much consistent with the video.
The simple reason why you always want to know what the police accuses you of before you admit to doing anything is that they might know less than you think. (That’s exactly why they ask you!) You should never lie to the police, you should just politely ask them why they stopped you. What’s wrong with that?