Automated-DNA sequencers are based on method developed by

The correct option is D Frederick Sanger
DNA sequencing is the process of determining the sequence of nucleotide bases (A, T, C, and G) in a piece of DNA.
Sanger sequencing, also known as the “chain termination method”, is a method for determining the nucleotide sequence of DNA.
It generates nested set of labelled fragments from a template strand of DNA to be sequenced by replicating that template strand and interrupting the replication process at one of the four bases.