In paragraph 11, which detail does the author use to develop the idea that significant changes are about to take place?

The author describes the narrator

..noticing that Monsieur Hamelis dressed up and the usually empty benches were filled with townspeople

..focusing on the old spelling-book with gnawed edges that Hauser was reading while sitting on the bench

..stepping over the bench to sit down at his desk before Monsieur Hamel notices he is late yet again

..admiring the quality of the blue coat and black embroidered breeches Monsieur Hamel is wearing

The passage "(11) I stepped over the bench and sat down at once at my desk. Not until then, when I had partly recovered from my fright, did I notice that our teacher had on his handsome blue coat, his plaited ruff, and the black embroidered breeches, which he wore on days of inspection or of distribution of prizes. Moreover, there was something extraordinary, something solemn about the whole plass. But what surprised me most was to see at the back of the room, on the benches which were usually empty, some people from the village sitting, as silent as we were: old Hauser with his three-cornered hat, the ex mayor, the ex-postman, and others besides. They all seemed depressed; and Hauser had brought an old spelling-book with gnawed edges, which he held wide-open on his knee, with his great spectacles askew."