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
Which of following is a microfilament ? 
Select and explain. 
A. Tubulin, B. Actin, C. Desmin, D. Vimentin
B: Actin
Answer: B: Actin 
Explanation: Ans. is 'b' i.e., Actin