Which of the following is a group decision-making technique?

According to the PMBOK® Guide, group decision-making techniques are used to reach a conclusion when multiple alternatives or requirements are being evaluated. These are primarily utilized in the Collect Requirements and Validate Scope processes.

Plurality: This is a decision-making technique where a decision is reached by the largest block in a group, even if a majority is not achieved. For example, if there are three options and the votes are split $40\%$, $35\%$, and $25\%$, the option with $40\%$ wins.

Other Group Decision-Making Techniques:

Unanimity: Everyone agrees on a single course of action.

Majority: Support from more than $50\%$ of the members of the group.

Dictatorship: One individual makes the decision for the entire group.

Analysis of Other Options:

A. Brainstorming: This is a Data Gathering technique used to identify a list of ideas in a short period of time. It is used to generate options, not to decide which option to pursue.

B. Focus groups: This is also a Data Gathering technique. It brings together prequalified stakeholders and subject matter experts to learn about their expectations and attitudes about a proposed product or service.

C. Affinity diagram: This is a Data Representation technique. It allows large numbers of ideas to be classified into groups for review and analysis. It organizes ideas but does not function as a decision-making mechanism.