C. The model does not show the true size of an atom.
Explanation:
The model can be described or explained as a physical representation of an unseen or yet to build structure or substance. The model will show the aim of the people that want to create a thing.
In this sense, the limitation of a model is that it will not actually give you the true size of the thing it is being used to represent. This means that it won't give the through size of the atom.
