Answer:
Lenina remarks that all individuals from society are cheerful, paying little mind to their standing. As indicated by Foster, this satisfaction gets from their molding, and "even Epsilons perform vital administrations."
This leads Lenina to review a period in her adolescence in which she woke from rest and wind up mindful, out of the blue, of the molding and "the murmuring that had frequented every one of her dozes."