As the Participants for Your Focus Group Begin to Arrive

As the participants for your focus group begin to arrive, you notice that two of the participants seem to already be best friends. What is the best course of action?

A) allow both participants to stay but seat them next to one another so that they feel comfortable
B) allow both participants to stay but seat them directly across from one another, so they are less inclined to speak to one another
C) thank both participants for their time, but politely let them know that you can't have friends together in a group because it violates confidentiality rules, and ask which wants to stay and participate
D) politely ask that both participants to leave to avoid making them decide which will stay