Final answer:
The correct formula for calculating the frequency of radiation when an electron transitions between energy levels is D. v = DE/h, where 'h' is Planck's constant, and 'DE' represents the energy change.
Step-by-step explanation:
The correct equation to solve for the frequency of radiation emitted when an electron moves from a higher energy level to a lower energy level is E = hv, where E is the energy change, h is Planck's constant, and v is the frequency of the radiation.
Therefore, the correct answer is D. v = DE/h. In the equation, the value of Planck's constant is h = 6.626 × 10-34 J.s, and the change in energy, ∆E (Delta E), corresponds to the difference in energy levels that the electron moves between. The greater the energy change, the higher the frequency of the emitted radiation.