Take a look at the passage again:
Struggling up three flights of stairs, her arms filled with the heavy texts
for four classes, her backpack loaded with notebooks and other supplies.
Jamala huffed and puffed. Never again would
she register for all of her classes back-to-back on the same days of the
week.
You chose the second part, Jamala huffed and puffed. This part has a main clause: Jamala is the subject; huffed and puffed are the verbs. A fragment will not have a main clause.
Go back to the passage to try again.