This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
Which phase of the cell cycle is resistant to most chemotherapeutic agents, i.e., those that are classified as phase-specific? 
Select and explain. 
A. G0, B. G1, C. G2, D. M
A: G0
Answer: A: G0 
Explanation: .