To determine which category of land use you would least expect to find in Salem today based on the population trends over the years, we can consider the general trends in urban development and land use associated with population growth.
Typically, as a city's population grows, you would expect to see an increase in residential and commercial land use to accommodate more people and businesses. Industrial land use might also be present, especially in towns that develop economically, but it can vary based on local economic focus and industrial capabilities.
Agricultural land use is less likely to be prominent in urban areas as they grow and develop, particularly over a long time frame like 100 years, where urban sprawl tends to replace farmlands.
Based on this reasoning, and without the specific details of the population growth in Salem over the specified years, the category of land use you would least expect to find in Salem today is:
C. agricultural