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
In dividing cells, spindle is formed by : 
Select and explain. 
A. Ubiquitin, B. Tubulin, C. Laminin, D. Keratin
B: Tubulin
Answer: B: Tubulin 
Explanation: B i.e. Tubulin