This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Kidney, Subject name: Medicine
Presence of which of the following in the urine is diagnostic of glomerular injury- 
Select and explain. 
A. Bright red cells, B. 20% dysmorphic RBC's, C. 100RBC per high power field, D. Beta 2 micro globulin
B: 20% dysmorphic RBC's
Answer: B: 20% dysmorphic RBC's 
Explanation: Glomerular injury is characterised by the presence of RBC casts & dysmorphic erythrocytes in urine microscopy. Ref Harrison20th edition pg 292