Hint: Immunization has been practiced since hundreds of years ago. Smallpox vaccine was the first vaccine to be developed in 1798. However smallpox was globally eradicated in 1979 through organized operation of bulk smallpox immunization in the 18th and 19th centuries.
The disease smallpox has distraught mankind for over several centuries. But the significant effort of Edward Jenner and further progression from his accomplishments later on has made smallpox less worrisome in modern times. Hence in the west, Edward Jenner is considered as the founder of vaccinology. In the year 1796, he validated immunity towards the smallpox after inoculating cowpox virus (vaccinia virus) into an eight year old boy. This experiment was rather potentially fatal and hence unethical also.
He obtained pus cells from the cowpox lesions which were present on the diseased young milkmaid’s hand. He then scratched these cells onto the skin of the eight-year old boy. Although the child suffered mild illness after this scratch but he recovered soon. After this, the boy was inoculated with a smallpox sample. No symptoms of smallpox were obtained in the boy or in any of the individuals who came in contact with this boy. This led to the development of the smallpox vaccine by Edward Jenner.
On the other hand, Robert Brown discovered the presence of nucleus in a cell and Alexander Fleming discovered the first antibiotic which is known as penicillin. However, Robin Cook was an American novelist.
Hence, the correct answer is option (C).
Note: Molecular genetics is widely employed in vaccinology. It helps in developing new delivery methods for vaccines for example, viral vectors, DNA vaccines, topical formulations, etc. It also helps in development of vaccines having increased effectiveness.