______ assists in economic growth by increasing personal income and retail sales.

The correct answer highlights the role of industry in stimulating economic growth, which occurs through various channels such as increased personal income and retail sales. When industries establish or expand in a region, they create job opportunities that enhance personal incomes for the local workforce. As more individuals earn higher wages, their purchasing power increases, leading to greater retail sales as they spend their income on goods and services. This cycle of job creation and increased consumer spending positively impacts the overall economy of the community.

In contrast, while the development of local business can also contribute to economic growth, it does not have the same immediate and broad-reaching impact as industrial activities, which tend to be larger in scale and influence. Rezoning may facilitate economic growth by allowing for different types of land use, but it is more of a regulatory change rather than a direct driver of income and sales. Subdividing land can assist in providing space for development but does not directly correlate with increases in personal income or retail activity as industry does.