Hmmm, that is tough. I can tell you mine was version "A" though. ECS recommends version A as well if you plug in 4.8iS in the search filter.

BMW E53 X5 N62 4.8L Drivetrain Axles - 31607507402 - CV Boot Repair Kit - (Outer) - ES#51469

__________________
2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards