Explanation
The RACI (Responsible, Accountable, Consulted, Informed) matrix is used to document which resources are responsible for which tasks. The RACI matrix is a tool that helps to clarify roles and responsibilities on a project. It assigns a level of responsibility to each resource involved in the project. References: CompTIA Project+ Study Guide Section 3.4.
The project manager should use a RACI matrix to document which resources are responsible for which tasks.
A RACI matrix is a type of responsibility assignment matrix (RAM) that plots the roles and responsibilities of resources on a project team. RACI stands for Responsible, Accountable, Consulted, and Informed. A RACI matrix can help to clarify who does what on a project, avoid confusion and duplication of work, and improve communication and collaboration among team members.

A rollback plan, also known as a backout plan, is a strategy designed to reverse changes made during a project in case of failure or undesired results1. A rollback plan is a form of risk response that allows the project to restore the previous state and minimize the impact of the issue. A rollback plan is usually created during the planning phase and implemented during the execution or closing phase of the project. The other options are not correct because:
A compliance check is a process that ensures that the project meets the relevant standards, regulations, and requirements. A compliance check is not a risk response, but rather a quality control or assurance activity.
A release plan is a document that outlines the scope, schedule, and resources for delivering a product or service to the customer. A release plan is not a risk response, but rather a communication or scope management tool.
A validation check is a process that verifies that the project deliverables meet the customer's needs and expectations. A validation check is not a risk response, but rather a quality control or assurance activity. Reference = CompTIA Project+ Study Guide: Exam PK0-005, 3rd Edition, Chapter 10: Executing and Closing Projects, page 314; CompTIA Project+ Certification Exam Objectives, Domain 3: Project Execution, Objective 3.2: Given a scenario, execute and monitor project tasks using traditional methodologies; Backout Plan - DevX

A QA plan, or quality assurance plan, is a document that specifies the quality standards, practices, resources, specifications, and activities for a product, service, project, or contract. A QA plan helps to ensure that the products produced during the project meet the highest quality standards and that the project objectives and customer requirements are met. A QA plan also helps to communicate the quality expectations and responsibilities to the team members and other stakeholders, and to monitor and control the quality performance throughout the project. Developing a QA plan is one of the key tasks ofthe project manager, as it is part of the project scope management and project quality management processes123. References = CompTIA Project+ Study Guide: Exam PK0-005, 3rd Edition, Chapter 3: Project Scope Management, p. 97; Chapter 5: Project Quality Management, p. 169; 6 Key Steps to Creating A Quality Assurance Plan - The QA Lead; What is Quality Planning? Quality Control Plans | ASQ; What Is A Quality Assurance Plan? - Sofeast

Incorrect configuration was the initial cause of the issue that caused the unexpected crash of the website that
the team was developing. The diagram given is an example of a fishbone diagram or a cause-and-effect
diagram that shows the possible causes of a problem or effect. The diagram has four main categories: people,
process, technology, and environment. Each category has subcategories that list specific factors that may
contribute to the problem or effect. The diagram shows that incorrect configuration under technology was
marked as an initial cause of website crash.

The project manager should use a change control log to document the effects of the hurricane delay on the
project. A change control log is a tool that records and tracks any changes that occur during the project
lifecycle. It usually includes information such as change ID, description, impact, status, approval, and
resolution. A change control log can help to monitor and manage the changes that affect the project scope,
schedule, cost, quality, or resources and ensure that they are aligned with the project objectives and
stakeholder expectations.