Browsing: communion

When discussing online churches that never gather in one physical location, two questions that often come up are

How do you do baptisms?
How do you celebrate communion?

In SimChurch, Douglas Estes does an excellent job of looking at the various options online churches have for the sacraments. He breaks them down into 4 categories.

Which if any of these expresses of baptism and communion are (most?) biblical and why?