1. The problem statement, all variables and given/known data refer to the question 2. Relevant equations 3. The attempt at a solution from figure b , moving to the right, we know that the wavelength increases. since e= hc/λ , so the energy diffrenece should be increases as going to the right, so i consider line 1,2 and 3 is in a specific series , and 4,5 in another series. line 1,2,3 should have higher energy difference , the question ask for electron transition ftom E1 to E0 . So , my ans is line 3 . but the line 3 is not choice for this question. the ans is line 5 . why?