Answer: Bureau of Public Housing.
Explanation: Urbanization simply means an increase in the number of people that reside in urban areas. It involves migration from rural(country side) to urban(cities) areas which results in an increase in the number of people in urban areas.
A city experiencing rapid urbanization means the rate of migration from rural areas is on a high level. This would require more accommodation for the new immigrants.
Therefore, the Bureau of Public Housing is most likely to need additional workers because rapid urbanization means insufficient housing for people to live in.
The Bureau of Public Housing is most likely to be overwhelmed with work trying to create housing regulations and making sure immigrants are provided houses to live in.