Which of the Following Would Not Be Considered Unobtrusive Measures

Multiple Choice

Which of the following would not be considered unobtrusive measures?

A) Malls tracking patrons through their Smartphones so stores can send them targeted ads.
B) Face-recognition cameras at kiosks that classify people by age and sex and post targeted ads.
C) Bionic mannequins that greet customers' and ask them targeted questions about their purchasing habits.
D) Cameras that follow you through the store recording your every move.