- AOver the same year, accidents fell by about the same percentage on comparable highway stretches in the region where no cameras were installed
- BThe speed cameras were expensive to purchase and install
- CSeveral drivers wrote to the council complaining about the cameras
- DA few of the cameras were out of order for about two weeks during the year
Step-by-Step Solution
If similar stretches without cameras improved just as much, the fall is explained by whatever was affecting the whole region, and the cameras add nothing to the explanation. Cost and complaints say nothing about whether accidents fell because of the cameras, and a brief outage would if anything understate their effect.
Answer: A) Over the same year, accidents fell by about the same percentage on comparable highway stretches in the region where no cameras were installed