What technique can be used to unite spatially and temporally separate participants in a text-based group discussion via email?

A) Computer Assisted Telephone Interviewing (CATI)
B) Virtual Focus Groups
C) Web-Based In-Depth Interviewing
D) Email-Based In-Depth Interviewing

Virtual Focus Groups are the most suitable technique for uniting spatially and temporally separate participants in a text-based group discussion via email. This technique enables participants to communicate with each other in real-time through digital platforms such as video conferencing tools, chat rooms, and online discussion forums. This makes it possible for participants to interact as if they were in the same physical location, regardless of their geographical location or time zone. Other techniques, such as CATI, web-based in-depth interviewing, and email-based in-depth interviewing are not suitable for creating a sense of collaboration and real-time interaction among participants in a text-based group discussion.