The correct option is B Charles Darwin and Alfred Wallace
The theory of evolution by natural selection is a theory about the mechanisms of how organisms evolve from the pre-existing organisms. There were many different theories postulated regarding evolution, but the basic theory of evolution by natural selection is the most accepted one.
Charles Darwin independently documented the theory of evolution by natural selection with evidence he gathered in 5 years on HMS Beagle. His ideas on evolution were not very accepted by the elite established scientists, so he began establishing friendships with younger men who were on the rise like Thomas Huxley, Joseph Hooker etc.
Over a period of many years, through correspondence, he tried to convince them with his ideas. Later in the 1850s, he also started correspondence with Alfred Wallace who was working in the Malayan Archipelago. Wallace sent Darwin the details of his findings on evolution by natural selection. This led to the development of the theory of evolution by natural selection and finally both their papers were read together at the Linnean Society of London.