Ans.
Dideoxyribonucleotide chain termination method is a method of DNA sequencing, by which the order of nucleotide present in a DNA molecule, can be identified. This method was developed by Sanger that involves use of dideoxyribonucleotides (nucleotide that lack both 2' and 3'-OH groups).
The chain termination method is based on the selective incorporation of dideoxynucleotides during in vitro DNA replication of that gives idea about sequence of DNA of interest.
Thus, the correct answer is option B). 'sequencing DNA.'