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
Colloidal osmotic pressure in plasma is exerted mainly by? 
Select and explain. 
A. Albumin, B. Globulin, C. Fibrinogen, D. Transferrin
A: Albumin
Answer: A: Albumin 
Explanation: Albumin is single most important plasma protein help in maintaining osmotic pressure in plasma.