This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Haematology, Subject name: Pathology
Thrombosis seen in which stage of lupus nephritis? 
Select and explain. 
A. Class I, B. Class II, C. Class III, D. Class IV
C: Class III
Answer: C: Class III 
Explanation: Thrombosis is seen in class 3 ie Focal lupus nephritis. Affected gglomeruli may exhibit swelling and proliferation of endothelial and mesangial cells associated with leukocyte accumulation, capillary necrosis and hyaline thrombi. Ref:Robbins and Cotran Pathologic basis of disease.South Asia Edition-9 volume 1.page no.222