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: Physiology
A 50 year old female goes into shock and her blood pressure was 50 mmHg. Which of the following concerning her GFR is most likely? 
Select and explain. 
A. Myogenic autoregulation will keep GFR constant, B. Angiotensin II release will maintain normal GFR, C. The macula densa will cause constriction of the afferent aeriole to maintain GFR, D. GFR will viually cease
D: GFR will viually cease
Answer: D: GFR will viually cease 
Explanation: Once blood pressure drops below about 60 mmHg, GFR will basically cease, although a very small amount of filtrate may continue to be produced. This is another reason why maintaining blood pressure is so impoant.