A 51-year-old woman with a noncontributory medical history is being evaluated for Raynaud phenomenon of several years’ duration. Upon review of systems, she endorses heartburn and dysphagia for several months and mild shortness of breath with exertion. On examination, you note dilated nailfold capillary loops with areas of dropout, and reduced skin laxity over the dorsal fingers, hands, forearms, and upper arms as well as subtle sclerosis over the upper chest and upper back. Considering the most likely diagnosis, which of the following laboratory test would have the most prognostic significance in terms of her risk for severe renal involvement? A. Anticentromere antibody B. Anti–double-stranded DNA antibody C. Antinuclear antibody (ANA) D. Anti-RNA polymerase III antibody E. Antitopoisomerase I (anti-SCL-70) antibody Visit the link in our bio to submit your answer for CME credit!