New theories usually don't start "from scratch. For example, the
modern model of the atom is the result of new information added to the
cloud model. What is the main difference between the cloud model of
the atom and the modern model?
A. Only the modern model includes protons.
B. The cloud model does not include neutrons.
C. Electrons move in specific orbits in the modern model.
D. Electrons exist in a cloud around the nucleus in the cloud model.