This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Glomerular Filtration, Renal Blood Flow, and Their Control, Subject name: Physiology
All of the following decrease the Glomerular filtration rate except - 
Select and explain. 
A. Decreased plasma protein levels, B. Increased tubular hydrostatic pressure, C. Decreased effective filtration surface area, D. Decreased capillary hydrostatic pressure
A: Decreased plasma protein levels
Answer: A: Decreased plasma protein levels 
Explanation: Plasma protein binding of a substance decreases is glomerular filtration. Only unbound substances are filtered.