Both statements (I) and (II) align with the information provided in the passage. Statement (I) correctly connects urbanization and car usage to increasing pollution levels, while Statement (II) discusses the research conducted in China, showing the impact of pollution on test scores and the greater effect on language skills.
- Option (a) is correct, as urbanization and increasing car use are indeed linked to rising pollution levels.
- Option (b) correctly describes the research results on the effects of pollutants.
- Option (d) is incorrect because both statements are supported by the passage.
Thus, the correct answer is (c).