Identifying Electoral Systems that Reduce Wasted Votes

In a recent study analyzing the impact of various electoral systems on voter turnout and representation, researchers found significant differences when comparing plurality systems, runoff elections, and rank-choice voting. Consider the following question:

Which of the following electoral systems is most likely to mitigate the phenomenon known as 'wasted votes' and encourage greater voter engagement by providing voters with more options without the fear of their vote contributing to an ineffective outcome?