Trevor is considering having his attorney prepare a springing power of attorney in which he gives his friend, Ella, the power to handle his finances. In which situation should Trevor include such a document in his overall estate plan?

A$.$Ella is only $16$ years old.

B$.$Ella is legally incompetent.

C$.$In the event that Trevor becomes disabled, Ella will be able to pay Trevor's bills.

D$.$Trevor wants Ella to be able to handle all of his finances immediately.