The correct option is D lack of concern about weighty subjects
Option C is the correct answer. The poem addressing little girls going to school, illustrates their free spirit, having no worries or concerns about worldly things. Being young girls, they are not supposed to worry about matters beyond their comprehension, and the poet just confirms the same nature. As per options Band D, the poet doesn't explicitly convey their frailty or their inability to understand such things, neither do they suspect things contrary to their teachings, nor are they adept or wanting to disregard others' feelings. They are simply not interested in the weighty subjects they re taught and told. Thus, options A,B,D and E are incorrect.