Should the following be included in the category of fluid: milk (whole or skim), yogurt, soup?

The milk & the soup: I assume that you are having to watch your total daily fluid intake, and have been given a certain restriction - like 1500cc per day. I would count the milk and the soup liquid into your total fluid volume, but would count the yogurt more as a food. You basically need to be concerned about how much free water you are putting into your system, so count the thinner liquids and not the thicker foods.