The final step in a Sanger DNA sequencing reaction is to run the DNA fragments on a gel.What is the purpose of running DNA fragments on a gel?

A)It adds ddNTP to the end of each DNA fragment.
B)It changes the length of the DNA fragments.
C)It separates the DNA fragments based on their charge.
D)It separates the DNA fragments generated based on their size.
E)It adds dNTPs to the end of each DNA fragment.