Passage Summary: A highway started using electronic tolls, which made trips faster and cleaner for each car. Surprisingly, the total amount of smog from the highway didn't actually go down.

Reasoning: Electronic tolling reduced the time and pollution per individual trip, yet the total amount of air pollution from the highway remained the same.

Analysis: The conflict here is between a per-unit decrease and a total sum that remains unchanged. If each car is cleaner, but the total pollution is the same, there must be more units on the road now. Look for an explanation that suggests the improved traffic flow encouraged more people to use this highway instead of other routes. This is a classic LSAT scenario where an efficiency gain is offset by an increase in total volume.