article: Everybody has heard of fast food,but have you ever eaten slow food?Well,you might just want
  to try it. Here are some Americans talking about slow food.
  Karen:I'm very excited because I start to run my own business--a new snack bar called Good Food. It is special because we only have slow food. What is slow food? Well, it is more than just healthy food. Show food is also about growing food in a good way so that the environment is not hurt. Come and try my food--I think you'll like it.
  Mark: I'm a farmer from California. I grow food in a special way--a way that is better for the environment. I sell a lot of my food to the restaurants and snack bars in the city. And I also visit schools a lot and try to teach children about food, for some kids think that fast food is the only food.
  Joshua: I had the best lunch with my friend Susi in the slow food snack bar last Thursday, I had the great tomato and cheese salad--much better than a pizza and a Coke. A farmer came to our school to tell us about slow food . which I had never heard of before. And now I want to find out more about it on the Internet.. I think it's really a good idea. I hope they open more slow food restaurants soon
question: Who runs a slow food snack bar called Good Food?
options: Karen. Mark. Joshua. Susi.