Through the contrast between human and mechanical teachers, which aspect of education does the story question?

Correct answer: Whether learning can be completed by efficiency alone

The governing concept is the difference between efficient instruction and complete education. The mechanical teacher can deliver material in a controlled and individualized way, but the story asks whether speed, accuracy, and programmed efficiency are enough when learners also need interaction, encouragement, understanding, and a sense of community. Therefore option A is correct. Option B is a minor descriptive detail about old books, not the central educational issue. Option C concerns the home environment, and option D makes an unsupported claim that marks are unnecessary. The story does not reject technology completely; it questions whether technology alone can provide the human dimension of learning.