The correct option is
C Demography
Anthropology is the study of humans in the past and present. It draws on the humanities as well as social, biological, and physical sciences.
Sociology is the scientific study of social behavior or society, including its origins, development, organization, networks and institutions.
Geography is a field of science devoted to the study of the lands, the features, the inhabitants, and the phenomena of Earth.
Demography involves the statistical study of human populations. Demographers seek to understand population dynamics by investigating three main demographic processes mainly birth, migration, and ageing (including death). All three of these processes contribute to changes in populations, including how people inhabit the earth, form nations and societies, and develop culture.
So, the correct answer is option C.