The characteristic bright–line spectrum of potassium is produced when electrons A) jump to higher energy levels
B) return to lower energy levels
C) are lost by neutral potassium atoms
D) are gained by neutral potassium atoms
E) are released from the nucleus

B.

Explanation:

When the electron changes levels, it decreases energy and the atom emits photons. The photon is emitted with the electron moving from a higher energy level to a lower energy level. The energy of the photon is the exact energy that is lost by the electron moving to its lower energy level.

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the answer is minerals.