Consider the following spatial arrangements of the octahedral complex ion `[Co(NH_(3))_(4)CI_(2)]^(o+)`
Which of the following statements is incorrect regarding these structures?
(a) I and II are enantiomers
(b) II and III are cis and trans isomers respectively
(c) III and IV are trans and cis isomers respectively
(d) II and IV have identical structures .