Which constitutional amendment established the procedures for presidential succession?

The 25th Amendment is the correct choice because it directly addresses the procedures for presidential succession, outlining what happens if a president is unable to perform their duties due to death, resignation, removal from office, or incapacitation. This amendment clarifies the line of succession, specifying that the vice president assumes the presidency in these circumstances, and it also lays out the process for filling a vacancy in the vice presidency. This structure ensures continuity in government and a clear framework for managing unexpected transitions in leadership.

The other amendments mentioned do not deal with presidential succession. The 22nd Amendment relates to term limits for the presidency, the 12th Amendment specifies the process for electing the president and vice president, and the 20th Amendment addresses the terms of office for federal officials and the procedures for transitioning between outgoing and incoming administrations. Each of these focuses on different aspects of the governmental framework and does not establish protocols for succession like the 25th Amendment does.