A 41 year old female comes to your office with a complaint of blurry vision over the past one year. On physical exam, you note keratoconjunctivitis and atrophy of the oral mucosa. You decide to biopsy a section of her lip which shows lymphocytic and plasma cell infiltrates in the salivary glands. Which of the following autoantibodies is most likely to be identified on laboratory testing?
d. Anti-double stranded DNA