Question

What must occur when an electron in an atom returns from a higher energy state to a lower energy state?(1) A specific amount of energy is released

(2) A random amount of energy is released
(3) The atom undergoes transmutation
(4) The atom spontaneously decays

Answer 1

"A specific amount of energy is released" is what must occur when an electron in an atom returns from a higher energy state to a lower energy state. It takes energy to go the other direction. 

Answer 2

Answer : Option A) A specific amount of energy is released

Explanation : When an electron gets excited it jumps to the next energy level and on removal of the excitation energy source it comes back to its original state which is ground state, but while it comes back it emits a specific amount of energy and then it rests at the stable state. The energy can be florescence or phosphorescence depending upon the timing of emission of energy from the electron.