Final answer:
The individual who engages another to act on their behalf is known as the principal. The principal is associated with business law and warrants understanding in agency relationships, differing from a testator or a customer.
Step-by-step explanation:
The individual who engages another to act on their behalf in a business context is known as the principal. The principal is a party who gives authority to another individual, called an agent, to act on their behalf. The agent is then expected to perform tasks or make decisions within the scope of their granted authority. Understanding the roles of principal and agent is crucial in business law, especially when dealing with contracts and agency relationships.
The options provided in the question suggest different roles: A testator is someone who has created a will, and a customer is a person or organization that pays for goods or services. While all four terms are significant in various legal and business contexts, only the term principal directly refers to an individual who engages another to act for them.