When Large Signs Are Posted at Intersections in Berkeley,California,warning Drivers

Multiple Choice

When large signs are posted at intersections in Berkeley,California,warning drivers of the amount of the fine that will be imposed on them if they run a red light and it is photographed by cameras posted at this intersection,this is an example of:

A) a closed observation.
B) an open observation.
C) mystery shopping.
D) a descriptive study.
E) a disguised observation.