A 21-Year-Old College Student Presents to the University Campus Clinic

Multiple Choice

A 21-year-old college student presents to the university campus clinic. The nurse collects the patient's medical history and performs an initial assessment. The patient states, "I'm having a herpes flair, and I need a prescription for acyclovir." The nurse examines the lesion on the shaft of his penis. The ulcer is 2 cm in size and seems painless and hard upon palpation.
-How would the diagnosis of syphilis be confirmed?  

A) Dark-field microscopy
B) Blood antibody test
C) PCR
D) All of these tests can be used in diagnosis.