An odd situation came up in game 5 at WGC: my techmarine bolstered a ruin, causing it to grant 3+ cover. I then spread a squad of four out such that one guy is in the 3+ cover, two guys are out in the open, and a third guy is in a different piece of 4+ area terrain. An AP2 shot hits the unit from the side, so the only cover save available is the one granted by area terrain. What is the unit's cover save?
1) 3+: the majority of the unit (rounding up) is in cover, and the majority of the cover available (rounding up) is 3+
2) 4+: the majority of the unit (rounding up) is in cover, but only 1/4 of the squad is in the bolstered cover
3) None: 2 guys have no save, 1 guy has 3+, 1 guy has 4+. The most common save is actually the guys who have no save at all.