Answer:
The answer is letter D, qualitative.
Explanation:
The collection of date will largely depend on the type of research or study that you have.
When it comes to "qualitative research," there are various ways to collect data such as interviews, group discussions that are focused, observational methods, etc. This kind of data collection is effective if you are looking for answers on why people are doing such an activity or behaving in such a situation.
So, in the situation above, Dr. Carlson is collecting "qualitative" data. He will then try to analyze the narrative answers coming from the respondents. The respondents participate by telling stories about their experience or opinion.
