Police Dispatch Receives Two Calls from Citizens at a Time

Police dispatch receives two calls from citizens at a time when the number of calls to dispatch outnumbers available patrol units.One reports an in-progress act of vandalism and the other reports a man waving a knife at a bus station.Dispatch immediately sends officers to the latter call.What is this practice called?

A) call slicing
B) call division
C) call stacking
D) call separating