The statement which describes why greenbelts have formed around the cities is: C. Residents expressed a need for mixed-income level housing.
A green belt can be defined as a policy that designates a land-use zone such as fields or parks around a town (city), where people are legally prohibited from erecting or building any structure e.g houses, factories, schools, etc.
This ultimately implies that, a green belt is a legal tool that is used in urban planning to effectively and efficiently manage and organize a town (city).
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