Answer:
D.ethnography.
Explanation:
Ethnography: The term ethnography is referred to as the phenomenon that studies different people in their specific environment by using several methods including face-to-face interviewing, participant observation, etc. A researcher being involved in ethnographic research spends several years in the place he or she id studying and also referred to as field. Ethnography is one of the qualitative research methods.
Example: Eye tracking, discovery forums, social media analytics, etc.
In the question above. the sociologist is conducting ethnography.