A tsar was the emperorship title used in Russia before the 1917 revolution, similar to a king with absolute power. The last tsar, Nicholas II, ruled until the monarchy was overthrown, reflecting the centralized authority similar to that of a governor or king in other regions. The role of a tsar contrasts significantly with modern democratic leadership structures like presidents or senators. ;
A tsar was a Russian emperor similar to a king, wielding immense power until the monarchy's overthrow in 1917. The last tsar, Nicholas II, ruled during a time of great turmoil leading to the Russian Revolution. Therefore, the correct answer to the question is A. king.
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