Biotechnology pioneers: Identify who is widely credited with perfecting the core methods of modern genetic engineering (recombinant DNA). Context: Focus on the 1970s breakthrough enabling DNA from different sources to be cut, joined, and cloned in bacteria. Choose the correct option.

Given data

• Target: Who perfected the foundational lab methods of genetic engineering.
• Era: early–mid 1970s; technique: recombinant DNA and plasmid cloning.

Concept / Approach
Identify the scientists credited with establishing the repeatable technique for cutting, ligating, and cloning DNA across species in bacteria.

Reasoning
Herbert Boyer and Stanley Cohen pioneered recombinant DNA technology (1973), enabling insertion and cloning of foreign genes in bacteria—an advance that effectively perfected practical genetic engineering workflows and launched modern biotechnology.

Eliminating distractors
Watson & Crick: DNA structure (1953); Mendel: heredity laws (19th century); Ehrlich: immunology/chemotherapy, not rDNA methods.

Final Answer
Herbert W. Boyer and Stanley N. Cohen.