Final answer:
A runoff election is most likely to occur in a majority election electoral system, where the winning candidate must have at least 50 percent plus one vote to be declared the winner. If no candidate achieves this majority, a runoff election is conducted between the top two candidates. Option Correct is 1.
Step-by-step explanation:
Among the given options, a runoff election is most likely to occur in an electoral system called the majority election. In this type of election, the winning candidate must have at least 50 percent plus one vote of the total vote to be declared the winner. If no candidate achieves this majority, a runoff election is conducted between the top two candidates.
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