正解:B
A written policy is the best way for a company to document a change that allows staff to work from home by means of formal request. A policy is a statement or guideline that defines the rules, standards, or procedures for an organization's actions, decisions, or behaviors. A policy can help an organization to achieve its objectives, comply with regulations, ensure consistency and quality, and communicate expectations and responsibilities. A written policy is a policy that is documented in a formal document that can be distributed, reviewed, updated, and enforced by the organization. A written policy can help a company to document a change that affects its staff, such as working from home, by specifying the criteria, process, benefits, limitations, and consequences of the change. References : The Official CompTIA IT Fundamentals (ITF+) Study Guide (FC0-U61), page 210.