Consider the following ion 1. Ni2+ 2. Co2+ 3. Cr2+ 4. Fe3+ (Atomic number : Cr = 24, Fe = 26, Co = 27 and Ni = 28) The correct sequence of increasing number of unpaired electrons in these ions is
(1) 1, 2, 3, 4
(2) 4, 2, 3, 1
(3) 1, 3, 2, 4
(4) 3, 4, 2, 1