Final answer:
A gas in a balloon is most likely to occupy the total volume and take the shape of a sealed container. This is due to the properties of gases which allow them to expand or compress to fit any enclosing space.
Step-by-step explanation:
In terms of substances that would take up the total volume and shape of a sealed container, it is important to understand the properties and behaviours of different states of matter, namely solids, liquids and gases. Gases like the one in a balloon is the most suitable answer. A gas has the ability to expand or compress to fit into its enclosure, in this case, a container. On the other hand, a solid block of wood and a pile of sand retain their own shapes and do not mold to the shape of the container. A liquid will take the shape of its container but will not necessarily occupy the total volume unless it is enough to fill the container up.
Learn more about States of Matter