Answer:
D. Slums
Slums are defined as unsafe and unhealthy homes and some of the examples are lack of windows, leaky walls as well as roofs.
Overcrowded homes are limited or access to basic services.
Migration are mainly caused by the different benefits so city offers the compassion greater prospects especially for the employment, health care as well as education.
Step-by-step explanation:
Concentrated employment in the rural areas for mining, quarrying, logging, oilfields, processing all of that, random local factories, power generation, and transportation infrastructure sustains towns and cities with most rural people, all but the largest farmers, having jobs