The correct answer is - C) military force.
The protests for democratic reformation of China in the Tiananmen square where not seen fondly by the Chinese government. They decided to use military force in order to destroy the protest, and it was not just to move the people away or scare them off, but it was very brutal. Lot of people that were protesting were actually killed the by the military, and that was supposed to serve as an example for any other people in the country that would try and do something like that.
The protest was dominated by young people, students in general, and unfortunately, their will for better and free life meant death for lot of them.