The coordination complex ${\left[\mathrm{Co}{\left({\mathrm{OH}}_2\right)}_6\right]}^{2+}$ has one unpaired electron, which of the following statements are true?

(i) The complex is octahedral.

(ii) The complex is an outer orbital complex.

(iii) The complex is diamagnetic.

• A

  (i) and (iii) only
• B

  (i), (ii) and (iii)
• Correct answer
  C

  (i) and (ii) only
• D

  (ii) and (iii) only

Hence, the correct answer is option: 'C'.