@xvu For a business domain, .org could be OK, but I've heard some people say that it's supposed to be used for non-profits only (though I don't think there is actually rule that's enforced).
.ca would be fine, IMO, but I guess there's a risk of alienating potential customers from other countries.
So...maybe of the options you've listed .xyz would be best? It's short and easy to remember, plus it's still unusual so it might be memorable?