This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
ANA (antinuclear antibody) is seen in all except? 
Select and explain. 
A. ST E, B. RA, C. Sjogren's syndrome, D. Systemic sclerosis
B: RA
Answer: B: RA 
Explanation: Ans. is 'b' i.e., RA