Margie likes the idea of the old school because what was present there?

Correct answer: Human teachers and classmates

The governing concept is the value of shared, human-centred education. After reading the old book, Margie imagines children going to a special building, learning together, and being taught by a real person. This appeals to her because her own lessons take place alone at home with a mechanical teacher. The presence of classmates would provide friendship, conversation, comparison, and a sense of belonging, while the human teacher could respond personally to the learners. Therefore option D is correct. Option A refers to the modern machine system, not the old school. Options B and C describe isolation, which is precisely what makes Margie's present education less attractive. Her curiosity reveals the story's admiration for social classroom learning.