The ones that come from the coco bean, and that is not allowed on the program. Any soda that contains caffeine can have non-desired results. Pop in moderation can be acceptable for the average person. You also get into the issue of regular sodas being pretty much all sugar, so that can be a source of empty calories for people. Simple sugars can also raise triglycerides.
Water is probably the most preferred fluid.
I don't think many Americans drink enough water a day. Your typical recommendation would be eight eight-ounce glasses of water. That's calorie and caffeine free, and is actually a nutrient your body needs. It's the most preferred fluid. Refined grains are going to be your sweets, ranging from something with a lot of table sugar to sodas, cakes, cookies, desserts, and that is including your white refined grains such as white rice, potatoes, white pasta.