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: Surgery
The plasma of hyperthyroid patient contains excess of: 
Select and explain. 
A. Protein bound thyroxine, B. Free thyroxine, C. Both, D. None
B: Free thyroxine
Answer: B: Free thyroxine 
Explanation: None