Explanation: A statement of work (SOW) is a document that defines the scope, objectives, deliverables, and expectations of a project or contract, such as a cloud migration project or contract. A statement of work can help establish the roles, responsibilities, and expectations of the parties involved in a project or contract, such as the cloud service provider (CSP) and the client. A statement of work can also help specify the details of the project or contract, such as the timeline, budget, quality standards, performance metrics, and payment terms. Therefore, a statement of work has the sole purpose of outlining a professional services engagement that governs a proposed cloud migration. Option B is the correct answer. Gap analysis, feasibility study, and service level agreement are not the best options to describe a document that has the sole purpose of outlining a professional services engagement that governs a proposed cloud migration, as they have different purposes and scopes. Gap analysis is a method of comparing the current state and the desired state of an application or workload, and identifying the gaps or differences between them. Gap analysis can help determine the requirements, challenges, and opportunities of migrating an application or workload to the cloud, but it does not define the scope, objectives, deliverables, and expectations of a cloud migration project or contract. Feasibility study is a comprehensive assessment that evaluates the technical, financial, operational, and organizational aspects of moving an application or workload from one environment to another. Feasibility study can help determine the suitability, viability, and benefits of migrating an application or workload to the cloud, as well as the challenges, risks, and costs involved. However, feasibility study does not define the scope, objectives, deliverables, and expectations of a cloud migration project or contract. Service level agreement (SLA) is a document that defines the level of service and support that a CSP agrees to provide to a client, such as the availability, performance, security, and reliability of the cloud service. SLA can help establish the service standards, expectations, and metrics that a CSP and a client agree to follow, as well as the remedies and penalties for any service failures or breaches. However, SLA does not define the scope, objectives, deliverables, and expectations of a cloud migration project or contract. References: CompTIA Cloud Essentials+ CLO-002 Study Guide, Chapter 7: Cloud Migration, Section 7.1: Cloud Migration Concepts, Page 2031 and What is a Statement of Work (SOW)? | Smartsheet