Catalyst for the End of the Cold War

By the late 20th century, the dynamics of the Cold War shifted significantly due to various factors, including geopolitical events and leadership changes in both the United States and the Soviet Union. Among the key events that contributed to the end of the Cold War was the strategic arms reduction negotiations and the increasing internal strife within the Soviet Union. Considering these factors, which of the following events is most commonly recognized as a major catalyst for ultimately leading to the dissolution of the Soviet Union and the Cold War?