Answer: C) institutional ethnography
Step-by-step explanation:
Institutional ethnography is described as the kind of study of carrying out a research on a particular process, study or environment. It's when a researcher takes time to learn of or study a process painstakingly. It was introduced by a Canadian known as Dorothy J. Smith in 1990's.
Dr Fielding is carrying out a research on stratification system in the United States and how it is perpetuated through time, the method he goes by the research proves he's using an institutional ethnography