Strangers were brought into a research lab and were instructed to discuss a personally meaningful topic in research conducted by Pryzbylski and Weinstein (2013)

Most of the time, doing that activity fosters a sense of closeness among strangers who are meeting for the first time. In this research, that closeness did not occur. Why not?
a. There was no physical contact between the strangers.
b. There was a mobile device on the table between the strangers.
c. One of the strangers had to leave the discussion abruptly.
d. The researchers didn't permit the strangers to speak freely.

Answer: B