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
Which of the following antibodies is most frequently seen in Antiphospholipid Syndrome? - 
Select and explain. 
A. Anti- beta 2 glycoprotein antibody, B. Beta 2 microglobulin antibody, C. Anti-nuclear antibody, D. Anti-centromere antibody
A: Anti- beta 2 glycoprotein antibody
Answer: A: Anti- beta 2 glycoprotein antibody 
Explanation: Antiphospholipid antibody syndrome has clinical manifestations including recurrent thrombosis,  repeated miscarriages,  cardiac valve vegetations and thrombocytopenia. Suspected Ab target include Beta 2 Glycoprotein 1, a plasma protein that associates with the surfaces of endothelial cells and trophoblasts.
Anti nuclear antibody and beta 2microglobulin Ab  seen in SLE.