After returning from a skiing trip to Colorado, a 24-year-old woman seeks medical attention for this eruption of sudden onset on her lip. She also has a sore throat and low-grade fever. She is otherwise healthy, and her only medication is an oral contraceptive.
What does this look like to you?
A. Staphylococcal impetigo.
C. Herpes simplex.
D. Lichen planus.
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