Question: Who was an adivisor to the eighth leader of the Soviet Union who died in 2006? 
Sentence (from "Dissolution of the Soviet Union"): On the previous day, Soviet President Mikhail Gorbachev, the eighth and final leader of the Soviet Union, resigned, declared his office extinct, and handed over its powers – including control of the Soviet nuclear missile launching codes – to Russian President Boris Yeltsin.
Relevant evidence: No