Final answer:
The sub-agency relationship develops when the sub-agent accepts the offer.
Step-by-step explanation:
The correct answer is B) The sub-agency relationship develops when the sub-agent accepts the offer.
When a blanket offer of sub-agency is given, the sub-agency relationship is not automatically formed. It only develops when the sub-agent accepts the offer and agrees to act on behalf of the principal agent. The acceptance creates a legal relationship between the two parties.
For example, if a real estate agent offers a blanket sub-agency to other agents in their office, the sub-agency relationship would only form when another agent accepts the offer and agrees to represent the principal agent's clients.