C. the office would remain vacant until the next presidential election
Before the 25th Amendment was ratified in 1967, if a vice president left office, the position would remain vacant until the next presidential election. The Amendment established a process for the president to nominate a vice president, subject to congressional approval, thereby ensuring the office would not go unfilled. As a result, the correct answer to the question is C: the office would remain vacant until the next presidential election.
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