Take a look at the passage again:
While Cynthia dressed for her sister's wedding, Murphy, the golden retriever,
ate the straps off the only shoes that matched Cynthia's pale blue dress.
Her replacement options were inappropriate.
Like rubber flip-flops, running shoes, fuzzy pink rabbit slippers, or brown
leather pumps.
You chose the second part, Her replacement options were inappropriate. This part has a main clause: options is the subject; were is the verb. A fragment will not have a main clause.
Go back to the passage to try again.