When compared with mall-intercept interviews, in-house interviews: are less expensive. are face-to-face interviews. are conducted in environments that are unfamiliar to respondents. are less convenient for researchers. are person-administered surveys?

I believe the answer is: are less convenient for researchers.

In mall intercept interview, there are a lot of potential subjects walking a rounding the area near them.

In an in-house interview, researchers need to make an effort to knock on the door, gain trust from the homeowners to enter their home and conduct the interview