The line graph shows air pollution levels in three cities—City A, City B, and City C—between 2010 and 2020. Overall, City A had the highest pollution levels throughout the period, while City C had the lowest. City B’s pollution levels increased over time, eventually approaching those of City A.
In 2010, City A had the worst air pollution, with a level of 80 µg/m³. However, pollution in this city gradually declined over the years, reaching around 65 µg/m³ in 2020. This suggests that the city may have taken measures to reduce air pollution.
City B had lower pollution levels at the beginning, with around 60 µg/m³ in 2010. However, the levels steadily increased, peaking at 75 µg/m³ in 2017. After that, there was a slight decline, but air pollution still remained high at 70 µg/m³ in 2020.
City C, in contrast, consistently had the lowest pollution levels. It started at 40 µg/m³ in 2010, rising slightly to 50 µg/m³ in 2015, before gradually decreasing to 45 µg/m³ by 2020. This indicates that air quality in City C remained relatively stable compared to the other two cities.
In conclusion, while City A saw an improvement in air quality, it remained the most polluted. City B’s pollution increased significantly, whereas City C had the least pollution, with only minor changes over time.