Answer:
Option A is true
Step-by-step explanation:
For option A, it's true because a map that has a scale model with the proportion of one centimeter to one kilometer is known as verbal scale which is a type of scale.
For option B, it's not true because though a scale model is most times always smaller than the object it represents, there are sometimes when the scale model is an enlarged view/representation of a small object.
For option C, it's true because there is no one scale that is confined to just a model. A model can use different scales to depict an object.