Explanation

Paul Berg is regarded as the father of genetic engineering because in 1972 at Stanford he created the first recombinant DNA molecules, splicing DNA from different organisms — the founding technique of the field — for which he shared the 1980 Nobel Prize in Chemistry. Philip Drinker invented the iron lung, Thomas Addison described adrenal insufficiency (Addison's disease), and Alpheus S. Packard Jr. was an entomologist. None of them worked on recombinant DNA, so B is the only correct answer.