Answer:
C. The boiling point of water
Step-by-step explanation:
We assume your question is the one attached.
Obviously, the shape of the (liquid) water is a function of the container it is in, as it is for any liquid or gas.
The rate of evaporation will depend on the temperature and on the surface area. The different containers are different in both ways, so evaporation is not a constant.
The boiling point is a physical property of the water, so will be the same across all containers.
The amount of steam released is related to the rate of evaporation. It will not be a constant across the different containers.
__
The appropriate choice is ...
The boiling point of water