Final answer:
Boris Yeltsin resigned due to unpopular reforms resulting in economic strife and corruption, ultimately leading to his replacement by Vladimir Putin in 1999.
Step-by-step explanation:
Boris Yeltsin resigned as president due to mounting dissatisfaction with his leadership, which was marred by corruption and the social costs of transitioning from the Soviet system. Despite initial popularity, Yeltsin's presidency faced challenges from economic hardship, political strife, and public disapproval, leading to his resignation in 1999. He was replaced by Vladimir Putin, who had risen to prominence under Yeltsin's tutelage and gained considerable influence in the political landscape of post-Soviet Russia.
As the first President of the Russian Federation, Yeltsin played a key role in the dissolution of the Soviet Union. His push for economic reforms resulted in significant social unrest and widened economic inequality. His early opposition to Communist hardliners was overshadowed by the negative consequences of rapid privatization, including the emergence of oligarchs. The economic crisis, combined with his declining health, made it difficult for Yeltsin to maintain authority, culminating in his voluntary resignation on December 31, 1999, favoring his chosen successor, Vladimir Putin.