Name a transition element which does not exhibit variable oxidation states

Sc

The correct answer is Option (1) → Sc

The transition element that does not exhibit variable oxidation states is:

✔ Scandium (Sc)

Sc shows almost exclusively the +3 oxidation state.

Why others show variable oxidation states:

• Mn (Manganese): Shows +2, +3, +4, +5, +6, +7 (maximum range)
• Fe (Iron): +2 and +3 (common), also +6 in some compounds
• Cu (Copper): +1 and +2