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
Colistin is obtained from ? 
Select and explain. 
A. Bacteria, B. Fungi, C. Actinmycetes, D. Herbs
A: Bacteria
Answer: A: Bacteria 
Explanation: Ans. is 'a' i.e., Bacteria Amongst the given options no drugs is obtained from fungus. Antibiotics are obtained from - 1. Fungi - Penicilllin, Cephalosporin, Griseofulvin. 2.Bacteria - Polymyxin B, Colistin, Bacitracin, Tyrothricin, aztreonam. 3. Actinomycetes - Aminoglycosides, Tetracyclines, Chloramphenicol, macrolides, Polyenes.