Answer:

D.

Step-by-step explanation:

A combination of interviewing, surveying, and observing, a focus group is a data collection method that involves several individuals who have something in common. The purpose of a focus group is to add a collective element to individual data collection.

A focus group study can ask participants to watch a presentation, for example, then discuss the content before answering survey or interview-style questions.

Focus groups often use open-ended questions such as, “How did you feel about the presentation?” or “What did you like best about the product?” The focus group moderator can ask the group to think back to the shared experience, rather than forward to the future.

Open-ended questions ground the research in a particular state of mind, eliminating external interference. 

Answer:

d.focus group is the answer.

hope it helps