Answer:
Although there is no omnipresent and controlling being in the whole world today, we can say that all human beings are controlled at some point.
Explanation:
Big Brother is someone who has all the control and can see everything in George Orwell's novel.
Today there is no such thing, but nevertheless we can say that all our actions are controlled.
Each citizen is controlled by his rulers or must carry out the laws that they impose as well as obey the police.
At another point we can say that we are being controlled by technology, things like voice searches or ads that appear after we talk about a certain topic with someone.
This could be seen a bit like the novel where a Big Brother is watching us.