Brooklenstuart0909go Brooklenstuart0909go Chemistry Answered 4. Which of the following ground-state electron configurations represents the atom that has the lowest first-ionization energy? (A) 18² 28¹ (B) 1s² 2s22p² (C) 1s² 2s²2p6 (D) 1s2 2s22p 3s¹