A、To take whatever drink being served. B、To ask for the drink you like best. C、To have soft drinks rather than alcoholic drinks.

In general, American food is mild tasting; most Americans do not season their food to any great degree. Salads are very popular and are served all year, but especially in the summer. Waiters tend to assume that everyone drinks coffee, but simply tell them if you wish something else. If a waiter says "Now or later?" he means "Do you want coffee with your meal or after it?" Many, but certainly not all, Americans drink coffee or tea with their meals. Either way is perfectly acceptable. When dining out, you can ask for tea, milk, "coke", wine or beer if you prefer. Restaurants can only serve beer, wine, or other alcoholic drinks if they have a license, that is, permission from the local government to serve alcoholic drinks. Normally, when eating in a private home, it is considered better manners to take whatever is being served and not to ask for something different, unless the hostess gives you a choice.
    The main course served in American meals is usually meat, fish, or poultry, but rarely is more than one of these served at the same meal. Seafood is sometimes served as a first course, however.