How do I convince my parents to let me have a bunny?

I have 1 dog, and 2 cats. I also have 2 fish. I really want a bunny because they are cute and sweet. My parents don't want one because they say that they are smelly and that they will be the ones taking care of it. I will pay for all of its stuff and the bunny and take care of it. My mom still isn't convinced and every time i ask my dad he says that the only reason to buy one is so he can eat it!!!! How to i convince them to let me by one?