Answer:
electron loses energy as it transitions to lower energy level
Explanation:
An atom is capable of absorbing and releasing electrons. The atom of a substance is said to be at its GROUND LEVEL STATE when it contains the lowest energy level. However, when it absorbs or takes in energy, it moves to a high energy level called EXCITED STATE. This level is unstable and hence, subject to declination.
Due to the instability of the excited state of an atom, it tends to lose the absorbed electrons and in the process of doing so, it emits or produce light. Therefore, according to this question, light is produced by an atom when the electron loses energy as it transitions to lower energy level i.e excited state to ground level state.