A role of a formal review is B. Moderator. A formal review is a type of static technique that involves a structured process of examining code or other software artifacts by a team of reviewers who follow predefined roles and rules. A formal review has four main phases: planning, preparation, meeting, and follow-up. A formal review has five main roles: author (the person who created the code or other software artifact under review), moderator (the person who leads and facilitates the review process), reviewer (the person who examines the code or other software artifact under review and provides feedback), scribe (the person who records the issues and outcomes of the review meeting), and manager (the person who monitors and controls the review process). A moderator is a key role in a formal review because he or she is responsible for planning, organizing, conducting, and reporting the review activities and ensuring that the review objectives are met. A detailed explanation of formal reviews can be found in [A Study Guide to the ISTQB® Foundation Level 2018 Syllabus], pages 35-37.