After doing PCR on the same region between two individuals, you notice that each person's DNA yielded pieces of different sizes. Which of the following is the most likely explanation?

A. A mistake was made during the PCR.
B. A mistake was made during gel electrophoresis.
C. This is an example of VNTRs.
D. This is an example of RFLPs.
E. None of the other answer options is correct.