A twenty-one-year-old woman complains that regular, gentle brushing of her teeth is painful besides causing profuse bleeding. Oral examination reveals the loss of epithelium from the attached gingival of both arches. Which of the following dermatological problems is this patient most likely to have?
A. Benign mucous membrane pemphigiod
B. Chronic discoid lupus erythematosus
C. Pemphigus
D. Psoriasis