What's the best way to convince your parents to get a dog?

2 years ago we had to put my 13 year old dog, Sasha, down. I was so sad after that my life still isn't the same because I've had her since I was only a few months old. Now I want to get a new dog to help to fill the occasional emptiness I feel. I know no other dog can replace her, that would be impossible, but I would love to have a dog back in my life again. The only problem is my parents don't want one. They say because they don't want the hardwood floors to get damaged, but I've told them I would trim their nails so that wouldn't happen, but they keep coming up with different reasons why we can't get one. So the question is how can I convince them to get a dog.