The theory of natural selection was proposed by:

### Step-by-Step Solution **1. Identify the concept:** The question asks for the scientist credited with proposing the theory of natural selection. **2. Evaluate the contributors:** - **James Watson:** Famous for the co-discovery of the double-helix structure of DNA in 1953 alongside Francis Crick. - **Gregor Mendel:** Known as the 'Father of Genetics' for his work with pea plants, establishing the laws of inheritance. - **Jean-Baptiste Lamarck:** Proposed an earlier theory of evolution based on the 'inheritance of acquired characteristics' (e.g., a giraffe's neck stretching during its lifetime), which was largely superseded by Darwin's theory. - **Charles Darwin:** In his 1859 book *On the Origin of Species*, Darwin proposed **natural selection** as the mechanism by which evolution occurs. He observed that individuals with traits better suited to their environment are more likely to survive and reproduce. **3. Conclusion:** The theory of natural selection is synonymous with Charles Darwin. Final Answer: **Charles Darwin**