Which transition element does not exhibit variable oxidation state?

Which of the following transition elements does not exhibit variable oxidation states ?

Though Sc is a transition element, it does not exhibit variable oxidation state. Why ?

Transition metals show variable oxidation states due to tendency of ‘d’ as well as ‘s’ electrons to take part In bond formation:- Which element in the first series of transition elements does not exhibit variable oxidation states and why?

Name transition element which does not exhibit variable oxidation state.

Name the transition element which does not exhibit variable oxidation states .

Name a transition element which does not exhibit variable oxidation states.

Name a transition element which does not exhibit variable oxidation states.

Name a transition element which does not exhibit variable oxidation states.