Answer:
Estoppel
Step-by-step explanation:
An agency is created between two parties when one party, with consent of the other party assign a third party to act on his behalf under his control. This third party is called a agent.
Under agency by estoppel, if the principal (who appoints agent to undertake task) assigns a third party, instead of agent, to carry out a task. It is called an agency by estoppel. The principal cannot deny later that he had assigned the work to a third party.