We got back our english tests yesterday, in which i wrote that the CIA installed "surveillance systems" in the Watergate Hotel.
Now my English teacher says thats wrong, complaining that "surveillance" could be only used in connection with video recording. And since there were only microphones installed, surveillance is the wrong term, she says.
Now its hard to find that little difference out on your self, since google only spitts out rubbish.
So I ask you: Can a microphone recording system be called "surveillance system"?
Thanks in advance