4. There are technically no Dragons in this game, Dragons have 4 legs and 2 wings, while Wyverns have 2 legs and 2 wings (Like in Skyrim). Wyverns are a subspecies of dragon which normally has has four limbs. The wyvern has wings instead of arms, much like a bird or a pterosaur and also Wyverns have also been known for their body length, which is unusually longer than a dragon's.
Not in TES, they're called dragons here because there are no wyverns otherwise.
It's like saying there are no trolls in Skyrim just three-eyed gorillas because trolls only have two eyes...