Take a look at the sentence again:
Teresa was expecting a visit from her mother, so she spent the day cleaning
the shelves of the refrigerator, scrubbing mold from the bathroom tile grout,
and __________.
The blank requires a present participle phrase. You chose she removed dog hair from the sofa cushions, which is an entire main clause and thus causes a parallelism error. Before you continue, review the rules for parallel structure.
Go back to the sentence to try again.