Final answer:
Rhodium (Rh) typically has a higher ionization energy among the provided elements due to its position in the periodic table, which implies a higher nuclear charge and a stronger attraction to the valence electron. Therefore, the correct option is D.
Step-by-step explanation:
Ionization energy refers to the amount of energy required to remove an electron from an atom. The general trend in the periodic table shows that ionization energy increases moving up a group and moving from left to right across a period. Therefore, in determining which of the given options (Mo, Zr, Nb, Rh) has the largest ionization energy, one would have to consider their positions in the periodic table. Molybdenum (Mo), Zirconium (Zr), Niobium (Nb), and Rhodium (Rh) fall within the transition metals section, where the trend can sometimes be less uniform due to d-orbital involvement. Rhodium (Rh) generally would have a higher ionization energy compared to the other listed elements due to its higher nuclear charge and being further to the right in the periodic table. The higher nuclear charge results in a stronger attraction between the nucleus and the valence electron, thus requiring more energy to remove an electron.