An Emperor and Kings

Say a country has twenty leaders who want to rule the country.  Only one can rule at a time.  As the current leader, would it be best to...

Eliminate all who aspire to be rulers
Allow your rule to expire so others may rule
Deny further rule until you have a successor
Imprison/restrict others who want to rule or reduce them to poverty
Allow them to rule as governors or subordinate leadership positions

If you choose the last option, how do you prevent them from turning on you or revolting? 

>>12
That's the point, when scientists want to find something they perform tests and keep some factors the same and change others to see how the properties change. You are the equivalent of the yammering faggot who smells like body odour and diarrhea who somehow finds his way into a science conference room and declares in an incoherent manner "The tests you have performed would have never occurred in real life, therefore their results are incorrect and never happenned!".

Indeed this has never actually happenned, but you can look at similiar occurances in history, namely civil wars where by you would get a situation similiar to this to develop ideas about what would happen and the major factors involved.