Question

emission of light from an atom occurs when an electron
falls into the nucleus.
drops from a higher to a lower energy level.
moves within its atomic orbital.
jumps from a lower to a higher energy level.

Explanation:

When an electron drops from a higher to a lower energy level, it emits energy in the form of light. Electrons do not fall into the nucleus. Moving within the same orbital does not involve emission of light. Jumping from a lower to a higher energy level requires absorption of energy, not emission.

Answer:

drops from a higher to a lower energy level.