Narrative inquiry is a qualitative research design where written documents or conversations are interpreted about an event or a course of events that are chronologically related. Case study is close examination of an event or phenomenon in its context in a given time-period. Ethnography is a research design where a researcher analyzes common behaviors, language, and action models of an intact culture within their natural environment during a long time-span. Phenomenology is a research design to study participants’ experiences about a phenomenon they define. Grounded theory is a qualitative research design aiming to find out a general abstract theory about a process, action, or interaction grounded in participants’ standpoint. The correct answer is D.