I don’t know how to help you but good luck
Answer:
Matter always takes space (or has volume).
If I had to answer, I would go with C.) Two elements in the same group
I would choose C because elements in the same group have the same number of valence electrons. When elements have the same number of valence electrons, they are all willing to give/receive them in the same way. Therefore, if placed in water, they will combine with water the same way.
Hope this helps!
Li, Na, K, Ca, Fe, Cu, Sr