During which phase of the cell cycle would a problematic mutation leading to cancer most likely occur?

Question

cer

1. Mutations are errors in the DNA copying process. Cancer is often caused when mutations occur in the cell cycle. During which phase of the cell cycle would a problematic mutation leading to cancer most likely occur? 
2. G1 Phase
3. S Phase
4. G2 Phase
5. M Phase

Answer 1

So Egeg G.,

You have almost all the information you need for an answer, right there in the problem text. Cells are always trying to repair DNA damage. But they can't do that, if the DNA strands are separated already, or if the time interval until replication is too small. So when would a cell be most vulnerable, given that additional info (which you might well have been able to deduce on your own?)?

-- Cheers, -- Mr. d.