Why are COX-2 selective NSAIDs safer than non-selective NSAIDs?

a) Minimize effects on COX-1, which have beneficial effects - improve renal perfusion, allow tissue repair, stimulate gastric mucous and bicarb production
b) Pose no risk for GI ulceration
c) Pose no risk for Renal damage
d) Are safe for use in dehydrated patients
e) All of the above