The Lengthy Transfer of the Presidency from Umaru Musa Yar'Adua

The lengthy transfer of the presidency from Umaru Musa Yar'Adua to Goodluck Jonathan

A) occurred within the country's constitutional framework.
B) illustrated how the country has become one dominated by a competitive oligarchy.
C) came about without direct military intervention.
D) was brought about at least in part due to international and domestic pressure.
E) All of the above statements are true.