Doing personal interviews with holiday shoppers at an indoor mall is an example of research.
a. primary
b. interpersonal
c. secondary
d. professional

Correct A). Primary Research

Primary research is a type of research in which the researcher personally go and collect the data. They can personally conduct surveys, observations, interviews, and ethnographic research. Primary research is also called first-hand research. The data collected by the primary researcher are new and fresh data.

Hence, the correct answer would be option A.

I think it is B. Correct me if i'm wrong.

Hope this helps! :D