Given below are two statements :
Statement I : The number of pairs, from the following, in which both the ions are coloured in aqueous solution is 3.
[Sc³⁺, Ti³⁺], [Mn²⁺, Cr²⁺], [Cu²⁺, Zn²⁺] and [Ni²⁺, Ti⁴⁺]
Statement II : Th⁴⁺ is the strongest reducing agent among Th⁴⁺, Ce⁴⁺, Gd³⁺ and Eu²⁺.
In the light of the above statements, choose the correct answer from the options given below