The complex ion which has no d-electron in the central metal atom is :
Atomic number of Mn. Fe and Co are 25, 26 and 27 respectively. Which of the following inner orbital octahedral complex ions are diamangetic? (a) [Co(NH3)6]3+ (b) [Mn(CN)6]3− (c) [Fe(CN)6]4− (d) [Fe(CN)6]3−