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: Pharmacology
An antibiotic not acting on tubulin is ? 
Select and explain. 
A. Bleomycin, B. Colchicine, C. Paclitaxel, D. Vincristine
A: Bleomycin
Answer: A: Bleomycin 
Explanation: Ans. is 'a' i.e., Bleomycin Bleomycin (an anticancer antibiotic) does not act on tubulin.