The air stays cleaner. Cars can travel at faster speeds. The skills of the drivers improve. It becomes safer to drive on the roads.
I am hesitating between 4 options to answer the following question, which option should I choose?
Question: Cities control the amount of pollution that is allowed to come from cars. How does this most likely help people?
Possibilities:
- The air stays cleaner.
- Cars can travel at faster speeds.
- The skills of the drivers improve.
- It becomes safer to drive on the roads.

The air stays cleaner.