After Nerva,what was the "Elective Option" of appointing leaders in the Roman Empire?

Question

Quizplus · Accepted Answer

The "Elective Option" refers to the practice where the reigning emperor would choose his successor, often adopting them as his son to ensure a smooth transition of power. This method was notably used by Nerva, who adopted Trajan as his successor, setting a precedent for the adoptive succession that characterized the era of the Five Good Emperors.

After Nerva,what Was the "Elective Option" of Appointing Leaders in the Roman