A Patient Presenting with Nasal Congestion, Fever, Purulent Nasal Discharge

A patient presenting with nasal congestion, fever, purulent nasal discharge, headache, and facial pain begins treatment with amoxicillin-clavulanate. At a follow-up visit 10 days after initiation of treatment, the patient continues to have purulent discharge, congestion, and facial pain without fever. What is the next course of action for this patient?

A) A CT scan of the paranasal sinuses
B) A referral to an otolaryngologist
C) An antibiotic based on likely resistant organism
D) A trial of azithromycin