Answer:
air quality
Explanation:
The answer to this question is the option B, air quality. Beijing, China, Shanghai, China, Delhi, India and Mumbai, India are the two most populous cities in the two most populous cities in the world. These would not be the worst places in the countries to visit, they would actually be more good in terms of diversity due to being the epicenters of the countries. They are not changing rapidly in climate change, that would affect very hot communities and very cold communities. They have high levels of biodiversity like I had mentioned before. The answer to the question is air quality, because these are very populous cities, and because they have excessive populations, (Beijing and Shanghai have about 20 million, and Delhi and Mumbai around 30 million each) That is why they would have really bad air quality.
