The correct option is B Pacific ocean
The most interesting observations made by Darwin were at the Galapagos Islands, situated off the coast of the Pacific ocean near South America. One famous observation was on the Galapagos tortoises, and how they appeared very different from the tortoises found in Africa. However, they seemed to look much like tortoises in South America though the sizes were different. Darwin coupled this with his knowledge of how animal breeders selectively breed certain animals to enhance the desired traits. This led to the emergence of the theory of "Natural Selection".