Researchers use Census data to study:

Demographic trends
Social change
Economic patterns
All of the above

The correct answer is: d) All of the above

Census data is a valuable resource for researchers who study a wide range of topics, including demographic trends, social change, and economic patterns.

Demographic trends are changes in the size, composition, and distribution of a population. Census data can be used to track changes in population size, age structure, race and ethnicity, and other demographic characteristics. This information can be used to understand the changing needs of a population and to plan for future growth.

Social change is the process of transformation in social structures, social institutions, social behaviors, and social norms. Census data can be used to track changes in social attitudes, values, and behaviors. This information can be used to understand the impact of social change on individuals, families, and communities.

Economic patterns are the ways in which economic activity is organized and distributed. Census data can be used to track changes in employment, income, and poverty. This information can be used to understand the economic well-being of a population and to develop policies to promote economic growth.

In addition to these three broad areas, census data can also be used to study a variety of other topics, such as education, health, housing, and transportation.