Answer: A.One long bench had been brought in for the ten of us privileged to watch.
Irony is a rhetorical device and literary technique in which an event is presented in a radically different way than what is actually the case. In this example, the fact that the students are watching the bombing is described as a "privilege." However, the event is unpleasant in its nature, and most people would not want to watch it. Therefore, the description of the event as a "privilege" is meant to be ironic.