Which concept involves changing district boundaries to favor a specific outcome in elections?

The concept of gerrymandering specifically refers to the manipulation of district boundaries in order to favor one political party or group over another in elections. This practice can be used to create districts that maximize the electoral advantage for the party in power by either concentrating or diluting specific voter demographics. For instance, by drawing district lines that include a majority of voters from their party, legislators can secure more seats in the legislature.

In contrast, redistricting is a broader process that occurs every ten years, following the census, where district boundaries are adjusted to reflect changes in population. While redistricting can potentially include gerrymandering if done with that intention, it is not inherently a tactic aimed at electoral advantage like gerrymandering is.

Voter suppression refers to tactics used to discourage or prevent specific groups of people from exercising their right to vote, which is a different issue altogether. Electoral reform encompasses broader changes to the electoral system aimed at improving fairness and accessibility, rather than the specific manipulation of district lines. Thus, the correct answer identifies a particular strategy used within the political arena, highlighting its targeted nature.