Answer: perceived relationship
Explanation:
An agent is referred to as someone who is given authority by the principal and acts in his or her behalf and the agent is also under the control of such person.
From the question, the principal is Bob while Betty is his agent. The relationship that exist in thus case is the perceived relationship which means that the third party that us, the tenants in thus case believe that an agent is authorised by the principal to do a particular work such as collection of rent in this case but in reality thus doesn't exist. They ate not meant to pay to the manager in this case but they acted based on their perception and since the principal didn't complain, they continued doing it.