Final answer:
The term 'model' refers to a representation of an original object or system. In science, models simplify complex systems for better understanding and are not always directly observable.
Step-by-step explanation:
A model is a representation of an original object or system in 2 or 3 dimensions. Models, including equations, physical representations, and computer simulations, are used for various purposes in the scientific community. They help us understand systems that are too complex or impossible to observe directly. For instance, the Bohr model of the atom, despite being an oversimplification, is useful for explaining certain scientific observations like atomic spectra. Similarly, the kinetic theory of gases models a gas as composed of atoms and molecules, aiding in our understanding of gas behavior beyond our direct sensory observation.
Given the context, the correct completion for the sentence would be: A model is a representation of an original object or system in 2 or 3 dimensions. Models include Option 1: Representation.