The more you take, the more you leave behind. What am I? (it's not footsteps)

The logical answer would be footstep, but since that's not it, the only other thing I could think of would be breath.

since it is asking for her reaction to elnora's trouble at school you can rule out any answers with a positive response (b). then you can rule out (d), this is because it does not show the mother's reaction but the daughter's response. that leaves you with two options (a) and (c), by looking at the options you can rule out (c) because it isn't referring back to elnora's issues at school.