The correct option is B Substituted agent
Section 193 states, Agent’s responsibility for sub-agent appointed without authority—"Where an agent, without having authority to do so, has appointed a person to act as a sub-agent, the agent stands towards such person in the relation of a principal to an agent, and is responsible for his acts both to the principal and to third persons; the principal is not represented by or responsible for the acts of the person so employed, nor is that person responsible to the principal."