Determine the Energy of the Most Energetic $x$ -Ray You Can Get from an Electron Transition in a Can

Multiple Choice

Determine the energy of the most energetic $x$ -ray you can get from an electron transition in a heavy atom having 93 protons.

A) $0.865 \mathrm { eV }$
B) $5.19 \times 10 ^ { 7 } \mathrm { eV }$
C) $164 \mathrm { MeV }$
D) $118 \mathrm { keV }$