Does it a fly or a bee?

I encountered this remarkable insect on my previous photo hunt, at first I thought that this was definitely a bee because it also flies around a wedellia flower.

But after I searched more about this insect I found out that this is actually a fly. This insect is called Palpada agrorum a kind of hoverfly that usually feed on the nectar of the flower.

The way it has a bee-like appearance is maybe to get away from the predator that might prey on them.