I believe the term is prophage.
The answer is true they should have both
For the first question, i think the correct answer is A. Normal cells undergo apoptosis while cancer cells don't. For the second question, The answer is option B.<span> </span><span>Cell division has two checkpoints namely, G1
checkpoint and spindle assembly checkpoint. The checkpoint which determines if
division has properly occurred is the G1 checkpoint. At this point, is a damage
in the DNA is detected or the has not reach the optimum size, the cell is
stopped in G1 and is not allowed to proceed to further process.</span>
Sister chromatids have different alleles although carry same genes on same loci. So if it doesn't happen so, like if there are same alleles on sister chromatids then there is a problem in its formation. i.e., male and female alleles haven't contributed equally ( may be an error during their segregation process ). And obviously it doesn't happen in a real cell so we must understand this point. Because normally whenever it happens there's one half from the male and one half from the female. (i.e. maternal and paternal alleles contribute equally).
I hope you get the answer!!!
I think the answer is A hope this helps