Comparing Na and Ne: which one of these has a greater ionization energy?

Ne

Explanation:

Comparing Ne and Na, Neon atoms will have the greatest ionization energy.

The ionization energy is the energy required to remove the most loosely held electrons within an atom.

As we go down the group, ionization energy decreases due to increase in the atomic radiusAcross a period it increases from left to right So, since Ne is right of Na, it has a higher ionization energy. It is also an inert gas and they have high ionization energy

D. most models represent a real world object in a simpler way

Yes you are correct use the scientific method