Maps that show population density are Thematic maps.
Thematic map is basically used to represent particular themes for particular geographical area. For example, population variation, temperature variation or population density, average annual income, rainfall distribution etc. Thematic map is also called special purpose and this can be quantitative or qualitative.
Physical maps is option is not true because physical maps are used to depict topography or natural landscapes or geographical features of an area such as mountains, deserts, bodies of water etc.
