If you had to choose, would you rather get stung by a wasp or by a bee?
There's really no right answer! Wasps can each sting you multiple times, but with less toxicity in each hit. Bees can only sting you once each, but it's an all-in injection of venom, and they leave behind a painful barbed stinger.
Of course, there are different species of bees and especially wasps, with different venoms. Some stings are inarguably more painful than others.
(Hornets are much worse than either.)