This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General pathology, Subject name: Pathology
A 30 year old lady presents to the outpatient depament with an Erythematous butterfly rash on her checks. Which of the following antibodies should be assayed initially for her suspected condition - 
Select and explain. 
A. Anti-Ds-DNA, B. Anti-Ro-Antibody, C. Anti-Centromere-Antibody, D. Anti-mitochondrial-Antibody
A: Anti-Ds-DNA
Answer: A: Anti-Ds-DNA 
Explanation: Anti-dsDNA antibodies are a group of anti-nuclear antibodies (ANA) and their target antigen is double stranded DNA. Blood tests such as enzyme-linked immunosorbent assay (ELISA) and immunofluorescence are routinely performed to detect anti-dsDNA antibodies in diagnostic laboratories. They are highly diagnostic of systemic lupus erythematosus (SLE) and are implicated in the pathogenesis of lupus nephritis.