PLAB-0294

A 24-year-old man is evaluated for facial pain and fever lasting four days. Symptoms began with an upper respiratory tract infection accompanied by purulent nasal discharge; he then began to have pain over the right cheek and developed a fever of 38.4°C. On examination, he has a purulent nasal discharge and tenderness over the right maxilla. CT shows right maxillary sinusitis. Which of the following is the most appropriate antibiotic treatment for this patient?