(D). DNA fragments containing repeats are labeled with radioactive probes.


DNA fingerprinting can be defined as a process, which involves identification of DNA characteristics of an organism as unique in all organisms as fingerprints.

There are total five steps in DNA fingerprinting, which include isolation of DNA from the cells, digestion of DNA with restriction enzymes, separation of DNA fragments in agarose gel, transfer of DNA fragments to a blotting paper, and labeling of DNA fragments with radioactive probes of specific sequence to see the results.

Thus, the correct answer is option (D) as represents that last step of DNA fingerprinting.