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
Etoposide acts by - 
Select and explain. 
A. Inhibition of dihydrofolate, B. Inhibition of topoisomerase, C. Inhibition of purine synthesis, D. Inhibition of protein synthesis
B: Inhibition of topoisomerase
Answer: B: Inhibition of topoisomerase 
Explanation: Ans. is 'b' i.e., Inhibition of topoisomerase o Etoposide and teniposide are natural anticancer drugs. o They act by inhibiting topoisomerase II that leads to DNA strand breakage.