Final answer:
A work permit is the document that legally authorizes a person to take employment in another country.
Step-by-step explanation:
The document that legally authorizes a person to take employment in another country is a work permit. A work permit, also known as a work visa or work visa authorization, is a government-issued document that allows a person from one country to work legally in another country for a specified period of time. It typically requires an employer to sponsor the individual and provide proof of job offer, and the individual may be required to meet certain criteria such as skills, qualifications, or education.