Which type of authority allows an agent to perform on behalf of a principal without having formal permission?

Implied authority is the correct choice because it grants an agent the ability to act on behalf of a principal based on the nature of the relationship and the tasks expected of them, even without explicit permission. This type of authority stems from the actions and conduct of the principal, where it is understood that certain activities are necessary for the completion of the agent's tasks.

For example, if a principal hires an agent to manage their property, the agent may have implied authority to make decisions necessary for property upkeep, even if those specific decisions weren’t formally discussed. This trust enables the agent to operate effectively without needing to seek the principal's approval for every minor decision.

In contrast, agency authority encompasses both express and implied authority, whereas express authority is the explicit permission given to an agent through written or verbal instructions. Apparent authority arises when a third party perceives that an agent has authority to act on behalf of the principal, based on the principal's representations. Hence, implied authority specifically allows actions to be undertaken seamlessly within the expected boundaries of the principal-agent relationship.