When too many people cram into a small area, urban infrastructure

Câu hỏi :

When too many people cram into a small area, urban infrastructure can't be effective. There will be a (31) ________ of livable housing, energy and water supply. This will create overcrowded urban districts with no proper facilities. Currently, fast urbanization is taking place predominantly in developing countries where sustainable urbanization has little relevance to people's lives.