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
Effect of efferent aeriole constriction and afferent aeriole dilatation on GFR is? 
Select and explain. 
A. Increases, B. Decreases, C. No change, D. First increase then decrease
A: Increases
Answer: A: Increases 
Explanation: Increases REF: Ganong's 22" chapter 38 Increase in renal blood flow increases GFR. Afferent aeriole brings blood to the nephron hence its dilation will increase renal blood flow, and efferent aeriole takes blood away from the nephrons, hence its constriction will cause increase filtration, hence increase in GFR.