The answer is B: base employment.
Explanation for each option:
a. Household income: While household income is an important factor in determining the ability of individuals to purchase or rent properties, it is not the foremost factor. Household income is influenced by the availability of jobs and the level of wages, which are directly related to base employment.
b. Base employment: Base employment refers to the foundational jobs in an economy that drive economic activity and growth. These jobs are typically in industries that bring income into the region, such as manufacturing, technology, or tourism. Base employment is the foremost factor because it creates the demand for housing and commercial properties. When there are more jobs, people move to the area, increasing the need for both residential and commercial spaces.
c. Existing supply of properties: The existing supply of properties affects the market by influencing prices and availability, but it does not create demand. Demand is driven by factors such as employment and income levels.
d. Marketing: Marketing can influence the attractiveness of properties and help in selling or renting them, but it does not create the underlying demand. The demand is primarily driven by economic factors such as employment and income.
In summary, base employment is the primary driver of demand in a market because it directly influences the number of people who need housing and commercial spaces.