C
Below is a question with multiple-choice answers. Choose the correct option based on your reasoning.

### Question:
Many states require vehicles to be examined and to meet safety and pollution standards. What impact might vehicle inspections have on the environment?

### Choices:
A. The environment will not be polluted.
B. The environment will become more polluted.
C. Fewer pollutants will be released by vehicles.
D. Fewer pollutants will be produced by older vehicles.

### Answer:
