Here is the item again:

Coated with dust, (A) the blinds filtered shadowy light into Adrian's cluttered apartment, (B) where clothing and empty take-out boxes littered the floor. (C) As flies buzzed around rotting bananas on the kitchen counter.

You correctly realized that the period after floor was wrong. As flies buzzed around a rotting bunch of bananas ... is a subordinate clause. When you attach a subordinate clause to the end of a sentence, you generally need no punctuation.

To fix the problem, you chose to do this:

Coated with dust, the blinds filtered shadowy light into Adrian's cluttered apartment, where clothing and empty take-out boxes littered the floor as flies buzzed around rotting bananas on the kitchen counter.

You have correctly employed Punctuation Rule 1:

Main Clause + Ø + Subordinate Clause.

You deserve cheering fans!

Go to the next sentence.

HomeTermsExercises MOOCHandoutsPresentationsVideosRulesAboutShopFeedback