By what is technology's success limited in the story?

Correct answer: By absence of human relationships

The governing concept is the difference between technical efficiency and complete educational success. The mechanical teacher performs useful tasks: it gives lessons at home, follows a programme, and checks Margie’s work rapidly. These features show that technology succeeds in delivering and managing information. However, the story also presents Margie as isolated from classmates and human teachers; she does not receive the companionship, shared joy, encouragement, and relationships that make schooling a social experience. Thus option C is correct. The absence of human relationships limits the meaning of technological success, even when the machine functions efficiently. Options A and B are actually parts of the technology’s operation, while D is only a location and does not explain the deeper limitation.