The Balmer series of hydrogen lines lies in the visible region because all its transitions end at

Explanation

Transitions down to the second level involve energy differences that correspond to visible photons, which is why Balmer lines are the ones seen with a spectroscope in the laboratory. The Lyman series ends at n equals 1 and lies in the ultraviolet, since those energy gaps are larger. Paschen and the higher series end at n equals 3 or above and fall in the infrared.