What scenario would typically involve traffic obstruction?

The scenario that typically involves traffic obstruction refers to situations that directly affect the flow of vehicles on the roadway. A fallen tree blocking a roadway is a clear example of an obstruction, as it physically prevents vehicles from continuing. Similarly, a vehicle breakdown on a highway creates an obstruction because it can halt traffic flow, while a parade or public gathering can lead to road closures or re-routes to accommodate the event.

While a grizzly bear causing traffic problems may disrupt flow as drivers slow down or stop, it is not a direct obstruction in the sense of blocking a road or causing a traffic jam due to a fixed obstruction. The primary difference is that the presence of a bear might lead to an unusual driving situation, but it doesn't create a permanent barrier like a fallen tree or a vehicle in distress. Therefore, the most direct example of traffic obstruction that involves an actual blockage of the roadway is the fallen tree.