નીચે આપેલા લેન્થેનોઈડ્સસ પૈકી એક \(+4\) ઓક્સિડેશન અવસ્થા દર્શાવી ઉમદા વાયુની ૨ચના (વિન્યાસ) પ્રાપ્ત કરી શકે ? (૫રમામાણ્વીય ક્રમાંક : \(La =57, Ce =58, Eu =63\) અને \(Yb =70)\)

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.