The reason people moved to modern cities in China was Urbanization. As a result of the overcrowded conditions in cities, there was a SARS outbreak in 2002.
The reason why China has health concerns is because there are many people living in cities which makes it overcrowded. This happened as a result of urbanization.
The crowded conditions has led to the spread of several diseases such as SARS in 2002 and Co-vid in 2019 and 2020.
Find out more on SARS at https://brainly.com/question/19491082.
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