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: Dental
Which of the following is Expanded Poly tetrafloro ethylene GTR membrane: 
Select and explain. 
A. Osseoquest, B. Milipore, C. Atrisorb, D. Bioguide
B: Milipore
Answer: B: Milipore 
Explanation: None