Answer:
Fluorine.
Explanation:
Remember that the ionization energy increases from left to right, but decreases down a group, so as we know, it would increase from the bottom up. The trend in the periodic table looks like this:
The red line shows the trend when the ionization energy increases.
As you can see, in this case, the element that would have the largest ionization energy would be fluorine.
The answer is Fluorine.
