What type of line is used to guide traffic around obstructions on the roadway?

The correct response to the question is a transition line. Transition lines are specifically designed to guide traffic around obstructions on the roadway. These lines typically indicate changes in traffic patterns or the end of one type of road condition as vehicles navigate around obstacles, such as construction zones, accidents, or other roadway impediments.

Transition lines are visually distinct from other types of roadway markings and serve to alert drivers to the need for a change in behavior — often to slow down, change lanes, or prepare for a detour. Proper understanding and recognition of these lines are vital for maintaining safe driving practices, especially in areas where vehicles may need to adjust to unforeseen circumstances in their path.

Each of the incorrect options represents other types of lines used in traffic management but does not serve the specific purpose of guiding traffic around obstructions. For instance, a transmission line relates to power distribution rather than roadway management. A holding line may indicate where vehicles should wait, but it does not guide traffic around physical barriers. A center line typically marks the division between opposing lanes of traffic, helping to maintain lane discipline.