What sort of reference map would a researcher use to create a chloroplast map showing differences in the voting tendency of rural and urban areas

A researcher creating a chloroplast map showing differences in the voting tendency of rural and urban areas would likely use a population density map as a reference map. This type of map displays the distribution of people in different areas, which can be categorized as rural or urban. By overlaying voting data onto this population density map, the researcher can visually compare voting tendencies between rural and urban areas.

Additionally, the researcher may also use political party affiliation maps or election result maps as reference maps to help identify voting patterns and differences between rural and urban areas. These maps can provide specific information on how different areas voted in past elections and help the researcher identify any trends or differences related to population density.